generate markdown documentation

23 files changed, 7207 insertions, 0 deletions

diff --git a/vendor/github.com/cpuguy83/go-md2man/LICENSE.md b/vendor/github.com/cpuguy83/go-md2man/LICENSE.md
new file mode 100644
index 00000000..1cade6ce
--- /dev/null
+++ b/vendor/github.com/cpuguy83/go-md2man/LICENSE.md
@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2014 Brian Goff
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/vendor/github.com/cpuguy83/go-md2man/md2man/md2man.go b/vendor/github.com/cpuguy83/go-md2man/md2man/md2man.go
new file mode 100644
index 00000000..af62279a
--- /dev/null
+++ b/vendor/github.com/cpuguy83/go-md2man/md2man/md2man.go
@@ -0,0 +1,20 @@
+package md2man
+
+import (
+	"github.com/russross/blackfriday"
+)
+
+// Render converts a markdown document into a roff formatted document.
+func Render(doc []byte) []byte {
+	renderer := RoffRenderer(0)
+	extensions := 0
+	extensions |= blackfriday.EXTENSION_NO_INTRA_EMPHASIS
+	extensions |= blackfriday.EXTENSION_TABLES
+	extensions |= blackfriday.EXTENSION_FENCED_CODE
+	extensions |= blackfriday.EXTENSION_AUTOLINK
+	extensions |= blackfriday.EXTENSION_SPACE_HEADERS
+	extensions |= blackfriday.EXTENSION_FOOTNOTES
+	extensions |= blackfriday.EXTENSION_TITLEBLOCK
+
+	return blackfriday.Markdown(doc, renderer, extensions)
+}
diff --git a/vendor/github.com/cpuguy83/go-md2man/md2man/roff.go b/vendor/github.com/cpuguy83/go-md2man/md2man/roff.go
new file mode 100644
index 00000000..8c29ec68
--- /dev/null
+++ b/vendor/github.com/cpuguy83/go-md2man/md2man/roff.go
@@ -0,0 +1,285 @@
+package md2man
+
+import (
+	"bytes"
+	"fmt"
+	"html"
+	"strings"
+
+	"github.com/russross/blackfriday"
+)
+
+type roffRenderer struct {
+	ListCounters []int
+}
+
+// RoffRenderer creates a new blackfriday Renderer for generating roff documents
+// from markdown
+func RoffRenderer(flags int) blackfriday.Renderer {
+	return &roffRenderer{}
+}
+
+func (r *roffRenderer) GetFlags() int {
+	return 0
+}
+
+func (r *roffRenderer) TitleBlock(out *bytes.Buffer, text []byte) {
+	out.WriteString(".TH ")
+
+	splitText := bytes.Split(text, []byte("\n"))
+	for i, line := range splitText {
+		line = bytes.TrimPrefix(line, []byte("% "))
+		if i == 0 {
+			line = bytes.Replace(line, []byte("("), []byte("\" \""), 1)
+			line = bytes.Replace(line, []byte(")"), []byte("\" \""), 1)
+		}
+		line = append([]byte("\""), line...)
+		line = append(line, []byte("\" ")...)
+		out.Write(line)
+	}
+	out.WriteString("\n")
+
+	// disable hyphenation
+	out.WriteString(".nh\n")
+	// disable justification (adjust text to left margin only)
+	out.WriteString(".ad l\n")
+}
+
+func (r *roffRenderer) BlockCode(out *bytes.Buffer, text []byte, lang string) {
+	out.WriteString("\n.PP\n.RS\n\n.nf\n")
+	escapeSpecialChars(out, text)
+	out.WriteString("\n.fi\n.RE\n")
+}
+
+func (r *roffRenderer) BlockQuote(out *bytes.Buffer, text []byte) {
+	out.WriteString("\n.PP\n.RS\n")
+	out.Write(text)
+	out.WriteString("\n.RE\n")
+}
+
+func (r *roffRenderer) BlockHtml(out *bytes.Buffer, text []byte) { // nolint: golint
+	out.Write(text)
+}
+
+func (r *roffRenderer) Header(out *bytes.Buffer, text func() bool, level int, id string) {
+	marker := out.Len()
+
+	switch {
+	case marker == 0:
+		// This is the doc header
+		out.WriteString(".TH ")
+	case level == 1:
+		out.WriteString("\n\n.SH ")
+	case level == 2:
+		out.WriteString("\n.SH ")
+	default:
+		out.WriteString("\n.SS ")
+	}
+
+	if !text() {
+		out.Truncate(marker)
+		return
+	}
+}
+
+func (r *roffRenderer) HRule(out *bytes.Buffer) {
+	out.WriteString("\n.ti 0\n\\l'\\n(.lu'\n")
+}
+
+func (r *roffRenderer) List(out *bytes.Buffer, text func() bool, flags int) {
+	marker := out.Len()
+	r.ListCounters = append(r.ListCounters, 1)
+	out.WriteString("\n.RS\n")
+	if !text() {
+		out.Truncate(marker)
+		return
+	}
+	r.ListCounters = r.ListCounters[:len(r.ListCounters)-1]
+	out.WriteString("\n.RE\n")
+}
+
+func (r *roffRenderer) ListItem(out *bytes.Buffer, text []byte, flags int) {
+	if flags&blackfriday.LIST_TYPE_ORDERED != 0 {
+		out.WriteString(fmt.Sprintf(".IP \"%3d.\" 5\n", r.ListCounters[len(r.ListCounters)-1]))
+		r.ListCounters[len(r.ListCounters)-1]++
+	} else {
+		out.WriteString(".IP \\(bu 2\n")
+	}
+	out.Write(text)
+	out.WriteString("\n")
+}
+
+func (r *roffRenderer) Paragraph(out *bytes.Buffer, text func() bool) {
+	marker := out.Len()
+	out.WriteString("\n.PP\n")
+	if !text() {
+		out.Truncate(marker)
+		return
+	}
+	if marker != 0 {
+		out.WriteString("\n")
+	}
+}
+
+func (r *roffRenderer) Table(out *bytes.Buffer, header []byte, body []byte, columnData []int) {
+	out.WriteString("\n.TS\nallbox;\n")
+
+	maxDelims := 0
+	lines := strings.Split(strings.TrimRight(string(header), "\n")+"\n"+strings.TrimRight(string(body), "\n"), "\n")
+	for _, w := range lines {
+		curDelims := strings.Count(w, "\t")
+		if curDelims > maxDelims {
+			maxDelims = curDelims
+		}
+	}
+	out.Write([]byte(strings.Repeat("l ", maxDelims+1) + "\n"))
+	out.Write([]byte(strings.Repeat("l ", maxDelims+1) + ".\n"))
+	out.Write(header)
+	if len(header) > 0 {
+		out.Write([]byte("\n"))
+	}
+
+	out.Write(body)
+	out.WriteString("\n.TE\n")
+}
+
+func (r *roffRenderer) TableRow(out *bytes.Buffer, text []byte) {
+	if out.Len() > 0 {
+		out.WriteString("\n")
+	}
+	out.Write(text)
+}
+
+func (r *roffRenderer) TableHeaderCell(out *bytes.Buffer, text []byte, align int) {
+	if out.Len() > 0 {
+		out.WriteString("\t")
+	}
+	if len(text) == 0 {
+		text = []byte{' '}
+	}
+	out.Write([]byte("\\fB\\fC" + string(text) + "\\fR"))
+}
+
+func (r *roffRenderer) TableCell(out *bytes.Buffer, text []byte, align int) {
+	if out.Len() > 0 {
+		out.WriteString("\t")
+	}
+	if len(text) > 30 {
+		text = append([]byte("T{\n"), text...)
+		text = append(text, []byte("\nT}")...)
+	}
+	if len(text) == 0 {
+		text = []byte{' '}
+	}
+	out.Write(text)
+}
+
+func (r *roffRenderer) Footnotes(out *bytes.Buffer, text func() bool) {
+
+}
+
+func (r *roffRenderer) FootnoteItem(out *bytes.Buffer, name, text []byte, flags int) {
+
+}
+
+func (r *roffRenderer) AutoLink(out *bytes.Buffer, link []byte, kind int) {
+	out.WriteString("\n\\[la]")
+	out.Write(link)
+	out.WriteString("\\[ra]")
+}
+
+func (r *roffRenderer) CodeSpan(out *bytes.Buffer, text []byte) {
+	out.WriteString("\\fB\\fC")
+	escapeSpecialChars(out, text)
+	out.WriteString("\\fR")
+}
+
+func (r *roffRenderer) DoubleEmphasis(out *bytes.Buffer, text []byte) {
+	out.WriteString("\\fB")
+	out.Write(text)
+	out.WriteString("\\fP")
+}
+
+func (r *roffRenderer) Emphasis(out *bytes.Buffer, text []byte) {
+	out.WriteString("\\fI")
+	out.Write(text)
+	out.WriteString("\\fP")
+}
+
+func (r *roffRenderer) Image(out *bytes.Buffer, link []byte, title []byte, alt []byte) {
+}
+
+func (r *roffRenderer) LineBreak(out *bytes.Buffer) {
+	out.WriteString("\n.br\n")
+}
+
+func (r *roffRenderer) Link(out *bytes.Buffer, link []byte, title []byte, content []byte) {
+	out.Write(content)
+	r.AutoLink(out, link, 0)
+}
+
+func (r *roffRenderer) RawHtmlTag(out *bytes.Buffer, tag []byte) { // nolint: golint
+	out.Write(tag)
+}
+
+func (r *roffRenderer) TripleEmphasis(out *bytes.Buffer, text []byte) {
+	out.WriteString("\\s+2")
+	out.Write(text)
+	out.WriteString("\\s-2")
+}
+
+func (r *roffRenderer) StrikeThrough(out *bytes.Buffer, text []byte) {
+}
+
+func (r *roffRenderer) FootnoteRef(out *bytes.Buffer, ref []byte, id int) {
+
+}
+
+func (r *roffRenderer) Entity(out *bytes.Buffer, entity []byte) {
+	out.WriteString(html.UnescapeString(string(entity)))
+}
+
+func (r *roffRenderer) NormalText(out *bytes.Buffer, text []byte) {
+	escapeSpecialChars(out, text)
+}
+
+func (r *roffRenderer) DocumentHeader(out *bytes.Buffer) {
+}
+
+func (r *roffRenderer) DocumentFooter(out *bytes.Buffer) {
+}
+
+func needsBackslash(c byte) bool {
+	for _, r := range []byte("-_&\\~") {
+		if c == r {
+			return true
+		}
+	}
+	return false
+}
+
+func escapeSpecialChars(out *bytes.Buffer, text []byte) {
+	for i := 0; i < len(text); i++ {
+		// escape initial apostrophe or period
+		if len(text) >= 1 && (text[0] == '\'' || text[0] == '.') {
+			out.WriteString("\\&")
+		}
+
+		// directly copy normal characters
+		org := i
+
+		for i < len(text) && !needsBackslash(text[i]) {
+			i++
+		}
+		if i > org {
+			out.Write(text[org:i])
+		}
+
+		// escape a character
+		if i >= len(text) {
+			break
+		}
+		out.WriteByte('\\')
+		out.WriteByte(text[i])
+	}
+}
diff --git a/vendor/github.com/russross/blackfriday/.gitignore b/vendor/github.com/russross/blackfriday/.gitignore
new file mode 100644
index 00000000..75623dcc
--- /dev/null
+++ b/vendor/github.com/russross/blackfriday/.gitignore
@@ -0,0 +1,8 @@
+*.out
+*.swp
+*.8
+*.6
+_obj
+_test*
+markdown
+tags
diff --git a/vendor/github.com/russross/blackfriday/.travis.yml b/vendor/github.com/russross/blackfriday/.travis.yml
new file mode 100644
index 00000000..a1687f17
--- /dev/null
+++ b/vendor/github.com/russross/blackfriday/.travis.yml
@@ -0,0 +1,30 @@
+sudo: false
+language: go
+go:
+  - 1.5.4
+  - 1.6.2
+  - tip
+matrix:
+  include:
+    - go: 1.2.2
+      script:
+        - go get -t -v ./...
+        - go test -v -race ./...
+    - go: 1.3.3
+      script:
+        - go get -t -v ./...
+        - go test -v -race ./...
+    - go: 1.4.3
+      script:
+        - go get -t -v ./...
+        - go test -v -race ./...
+  allow_failures:
+    - go: tip
+  fast_finish: true
+install:
+  - # Do nothing. This is needed to prevent default install action "go get -t -v ./..." from happening here (we want it to happen inside script step).
+script:
+  - go get -t -v ./...
+  - diff -u <(echo -n) <(gofmt -d -s .)
+  - go tool vet .
+  - go test -v -race ./...
diff --git a/vendor/github.com/russross/blackfriday/LICENSE.txt b/vendor/github.com/russross/blackfriday/LICENSE.txt
new file mode 100644
index 00000000..2885af36
--- /dev/null
+++ b/vendor/github.com/russross/blackfriday/LICENSE.txt
@@ -0,0 +1,29 @@
+Blackfriday is distributed under the Simplified BSD License:
+
+> Copyright © 2011 Russ Ross
+> All rights reserved.
+>
+> Redistribution and use in source and binary forms, with or without
+> modification, are permitted provided that the following conditions
+> are met:
+>
+> 1.  Redistributions of source code must retain the above copyright
+>     notice, this list of conditions and the following disclaimer.
+>
+> 2.  Redistributions in binary form must reproduce the above
+>     copyright notice, this list of conditions and the following
+>     disclaimer in the documentation and/or other materials provided with
+>     the distribution.
+>
+> THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+> "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+> LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+> FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+> COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+> INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+> BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+> LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+> CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+> LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+> ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+> POSSIBILITY OF SUCH DAMAGE.
diff --git a/vendor/github.com/russross/blackfriday/README.md b/vendor/github.com/russross/blackfriday/README.md
new file mode 100644
index 00000000..a6c94b79
--- /dev/null
+++ b/vendor/github.com/russross/blackfriday/README.md
@@ -0,0 +1,363 @@
+Blackfriday
+[![Build Status][BuildSVG]][BuildURL]
+[![Godoc][GodocV2SVG]][GodocV2URL]
+===========
+
+Blackfriday is a [Markdown][1] processor implemented in [Go][2]. It
+is paranoid about its input (so you can safely feed it user-supplied
+data), it is fast, it supports common extensions (tables, smart
+punctuation substitutions, etc.), and it is safe for all utf-8
+(unicode) input.
+
+HTML output is currently supported, along with Smartypants
+extensions.
+
+It started as a translation from C of [Sundown][3].
+
+
+Installation
+------------
+
+Blackfriday is compatible with any modern Go release. With Go and git installed:
+
+    go get -u gopkg.in/russross/blackfriday.v2
+
+will download, compile, and install the package into your `$GOPATH` directory
+hierarchy.
+
+
+Versions
+--------
+
+Currently maintained and recommended version of Blackfriday is `v2`. It's being
+developed on its own branch: https://github.com/russross/blackfriday/tree/v2 and the
+documentation is available at
+https://godoc.org/gopkg.in/russross/blackfriday.v2.
+
+It is `go get`-able via via [gopkg.in][6] at `gopkg.in/russross/blackfriday.v2`,
+but we highly recommend using package management tool like [dep][7] or
+[Glide][8] and make use of semantic versioning. With package management you
+should import `github.com/russross/blackfriday` and specify that you're using
+version 2.0.0.
+
+Version 2 offers a number of improvements over v1:
+
+* Cleaned up API
+* A separate call to [`Parse`][4], which produces an abstract syntax tree for
+  the document
+* Latest bug fixes
+* Flexibility to easily add your own rendering extensions
+
+Potential drawbacks:
+
+* Our benchmarks show v2 to be slightly slower than v1. Currently in the
+  ballpark of around 15%.
+* API breakage. If you can't afford modifying your code to adhere to the new API
+  and don't care too much about the new features, v2 is probably not for you.
+* Several bug fixes are trailing behind and still need to be forward-ported to
+  v2. See issue [#348](https://github.com/russross/blackfriday/issues/348) for
+  tracking.
+
+If you are still interested in the legacy `v1`, you can import it from
+`github.com/russross/blackfriday`. Documentation for the legacy v1 can be found
+here: https://godoc.org/github.com/russross/blackfriday
+
+### Known issue with `dep`
+
+There is a known problem with using Blackfriday v1 _transitively_ and `dep`.
+Currently `dep` prioritizes semver versions over anything else, and picks the
+latest one, plus it does not apply a `[[constraint]]` specifier to transitively
+pulled in packages. So if you're using something that uses Blackfriday v1, but
+that something does not use `dep` yet, you will get Blackfriday v2 pulled in and
+your first dependency will fail to build.
+
+There are couple of fixes for it, documented here:
+https://github.com/golang/dep/blob/master/docs/FAQ.md#how-do-i-constrain-a-transitive-dependencys-version
+
+Meanwhile, `dep` team is working on a more general solution to the constraints
+on transitive dependencies problem: https://github.com/golang/dep/issues/1124.
+
+
+Usage
+-----
+
+### v1
+
+For basic usage, it is as simple as getting your input into a byte
+slice and calling:
+
+    output := blackfriday.MarkdownBasic(input)
+
+This renders it with no extensions enabled. To get a more useful
+feature set, use this instead:
+
+    output := blackfriday.MarkdownCommon(input)
+
+### v2
+
+For the most sensible markdown processing, it is as simple as getting your input
+into a byte slice and calling:
+
+```go
+output := blackfriday.Run(input)
+```
+
+Your input will be parsed and the output rendered with a set of most popular
+extensions enabled. If you want the most basic feature set, corresponding with
+the bare Markdown specification, use:
+
+```go
+output := blackfriday.Run(input, blackfriday.WithNoExtensions())
+```
+
+### Sanitize untrusted content
+
+Blackfriday itself does nothing to protect against malicious content. If you are
+dealing with user-supplied markdown, we recommend running Blackfriday's output
+through HTML sanitizer such as [Bluemonday][5].
+
+Here's an example of simple usage of Blackfriday together with Bluemonday:
+
+```go
+import (
+    "github.com/microcosm-cc/bluemonday"
+    "gopkg.in/russross/blackfriday.v2"
+)
+
+// ...
+unsafe := blackfriday.Run(input)
+html := bluemonday.UGCPolicy().SanitizeBytes(unsafe)
+```
+
+### Custom options, v1
+
+If you want to customize the set of options, first get a renderer
+(currently only the HTML output engine), then use it to
+call the more general `Markdown` function. For examples, see the
+implementations of `MarkdownBasic` and `MarkdownCommon` in
+`markdown.go`.
+
+### Custom options, v2
+
+If you want to customize the set of options, use `blackfriday.WithExtensions`,
+`blackfriday.WithRenderer` and `blackfriday.WithRefOverride`.
+
+### `blackfriday-tool`
+
+You can also check out `blackfriday-tool` for a more complete example
+of how to use it. Download and install it using:
+
+    go get github.com/russross/blackfriday-tool
+
+This is a simple command-line tool that allows you to process a
+markdown file using a standalone program.  You can also browse the
+source directly on github if you are just looking for some example
+code:
+
+* <http://github.com/russross/blackfriday-tool>
+
+Note that if you have not already done so, installing
+`blackfriday-tool` will be sufficient to download and install
+blackfriday in addition to the tool itself. The tool binary will be
+installed in `$GOPATH/bin`.  This is a statically-linked binary that
+can be copied to wherever you need it without worrying about
+dependencies and library versions.
+
+### Sanitized anchor names
+
+Blackfriday includes an algorithm for creating sanitized anchor names
+corresponding to a given input text. This algorithm is used to create
+anchors for headings when `EXTENSION_AUTO_HEADER_IDS` is enabled. The
+algorithm has a specification, so that other packages can create
+compatible anchor names and links to those anchors.
+
+The specification is located at https://godoc.org/github.com/russross/blackfriday#hdr-Sanitized_Anchor_Names.
+
+[`SanitizedAnchorName`](https://godoc.org/github.com/russross/blackfriday#SanitizedAnchorName) exposes this functionality, and can be used to
+create compatible links to the anchor names generated by blackfriday.
+This algorithm is also implemented in a small standalone package at
+[`github.com/shurcooL/sanitized_anchor_name`](https://godoc.org/github.com/shurcooL/sanitized_anchor_name). It can be useful for clients
+that want a small package and don't need full functionality of blackfriday.
+
+
+Features
+--------
+
+All features of Sundown are supported, including:
+
+*   **Compatibility**. The Markdown v1.0.3 test suite passes with
+    the `--tidy` option.  Without `--tidy`, the differences are
+    mostly in whitespace and entity escaping, where blackfriday is
+    more consistent and cleaner.
+
+*   **Common extensions**, including table support, fenced code
+    blocks, autolinks, strikethroughs, non-strict emphasis, etc.
+
+*   **Safety**. Blackfriday is paranoid when parsing, making it safe
+    to feed untrusted user input without fear of bad things
+    happening. The test suite stress tests this and there are no
+    known inputs that make it crash.  If you find one, please let me
+    know and send me the input that does it.
+
+    NOTE: "safety" in this context means *runtime safety only*. In order to
+    protect yourself against JavaScript injection in untrusted content, see
+    [this example](https://github.com/russross/blackfriday#sanitize-untrusted-content).
+
+*   **Fast processing**. It is fast enough to render on-demand in
+    most web applications without having to cache the output.
+
+*   **Thread safety**. You can run multiple parsers in different
+    goroutines without ill effect. There is no dependence on global
+    shared state.
+
+*   **Minimal dependencies**. Blackfriday only depends on standard
+    library packages in Go. The source code is pretty
+    self-contained, so it is easy to add to any project, including
+    Google App Engine projects.
+
+*   **Standards compliant**. Output successfully validates using the
+    W3C validation tool for HTML 4.01 and XHTML 1.0 Transitional.
+
+
+Extensions
+----------
+
+In addition to the standard markdown syntax, this package
+implements the following extensions:
+
+*   **Intra-word emphasis supression**. The `_` character is
+    commonly used inside words when discussing code, so having
+    markdown interpret it as an emphasis command is usually the
+    wrong thing. Blackfriday lets you treat all emphasis markers as
+    normal characters when they occur inside a word.
+
+*   **Tables**. Tables can be created by drawing them in the input
+    using a simple syntax:
+
+    ```
+    Name    | Age
+    --------|------
+    Bob     | 27
+    Alice   | 23
+    ```
+
+*   **Fenced code blocks**. In addition to the normal 4-space
+    indentation to mark code blocks, you can explicitly mark them
+    and supply a language (to make syntax highlighting simple). Just
+    mark it like this:
+
+        ``` go
+        func getTrue() bool {
+            return true
+        }
+        ```
+
+    You can use 3 or more backticks to mark the beginning of the
+    block, and the same number to mark the end of the block.
+
+    To preserve classes of fenced code blocks while using the bluemonday
+    HTML sanitizer, use the following policy:
+
+    ``` go
+    p := bluemonday.UGCPolicy()
+    p.AllowAttrs("class").Matching(regexp.MustCompile("^language-[a-zA-Z0-9]+$")).OnElements("code")
+    html := p.SanitizeBytes(unsafe)
+    ```
+
+*   **Definition lists**. A simple definition list is made of a single-line
+    term followed by a colon and the definition for that term.
+
+        Cat
+        : Fluffy animal everyone likes
+        
+        Internet
+        : Vector of transmission for pictures of cats
+
+    Terms must be separated from the previous definition by a blank line.
+
+*   **Footnotes**. A marker in the text that will become a superscript number;
+    a footnote definition that will be placed in a list of footnotes at the
+    end of the document. A footnote looks like this:
+
+        This is a footnote.[^1]
+        
+        [^1]: the footnote text.
+
+*   **Autolinking**. Blackfriday can find URLs that have not been
+    explicitly marked as links and turn them into links.
+
+*   **Strikethrough**. Use two tildes (`~~`) to mark text that
+    should be crossed out.
+
+*   **Hard line breaks**. With this extension enabled (it is off by
+    default in the `MarkdownBasic` and `MarkdownCommon` convenience
+    functions), newlines in the input translate into line breaks in
+    the output.
+
+*   **Smart quotes**. Smartypants-style punctuation substitution is
+    supported, turning normal double- and single-quote marks into
+    curly quotes, etc.
+
+*   **LaTeX-style dash parsing** is an additional option, where `--`
+    is translated into `&ndash;`, and `---` is translated into
+    `&mdash;`. This differs from most smartypants processors, which
+    turn a single hyphen into an ndash and a double hyphen into an
+    mdash.
+
+*   **Smart fractions**, where anything that looks like a fraction
+    is translated into suitable HTML (instead of just a few special
+    cases like most smartypant processors). For example, `4/5`
+    becomes `<sup>4</sup>&frasl;<sub>5</sub>`, which renders as
+    <sup>4</sup>&frasl;<sub>5</sub>.
+
+
+Other renderers
+---------------
+
+Blackfriday is structured to allow alternative rendering engines. Here
+are a few of note:
+
+*   [github_flavored_markdown](https://godoc.org/github.com/shurcooL/github_flavored_markdown):
+    provides a GitHub Flavored Markdown renderer with fenced code block
+    highlighting, clickable heading anchor links.
+
+    It's not customizable, and its goal is to produce HTML output
+    equivalent to the [GitHub Markdown API endpoint](https://developer.github.com/v3/markdown/#render-a-markdown-document-in-raw-mode),
+    except the rendering is performed locally.
+
+*   [markdownfmt](https://github.com/shurcooL/markdownfmt): like gofmt,
+    but for markdown.
+
+*   [LaTeX output](https://bitbucket.org/ambrevar/blackfriday-latex):
+    renders output as LaTeX.
+
+
+TODO
+----
+
+*   More unit testing
+*   Improve Unicode support. It does not understand all Unicode
+    rules (about what constitutes a letter, a punctuation symbol,
+    etc.), so it may fail to detect word boundaries correctly in
+    some instances. It is safe on all UTF-8 input.
+
+
+License
+-------
+
+[Blackfriday is distributed under the Simplified BSD License](LICENSE.txt)
+
+
+   [1]: https://daringfireball.net/projects/markdown/ "Markdown"
+   [2]: https://golang.org/ "Go Language"
+   [3]: https://github.com/vmg/sundown "Sundown"
+   [4]: https://godoc.org/gopkg.in/russross/blackfriday.v2#Parse "Parse func"
+   [5]: https://github.com/microcosm-cc/bluemonday "Bluemonday"
+   [6]: https://labix.org/gopkg.in "gopkg.in"
+   [7]: https://github.com/golang/dep/ "dep"
+   [8]: https://github.com/Masterminds/glide "Glide"
+
+   [BuildSVG]: https://travis-ci.org/russross/blackfriday.svg?branch=master
+   [BuildURL]: https://travis-ci.org/russross/blackfriday
+   [GodocV2SVG]: https://godoc.org/gopkg.in/russross/blackfriday.v2?status.svg
+   [GodocV2URL]: https://godoc.org/gopkg.in/russross/blackfriday.v2
diff --git a/vendor/github.com/russross/blackfriday/block.go b/vendor/github.com/russross/blackfriday/block.go
new file mode 100644
index 00000000..7fc731d5
--- /dev/null
+++ b/vendor/github.com/russross/blackfriday/block.go
@@ -0,0 +1,1450 @@
+//
+// Blackfriday Markdown Processor
+// Available at http://github.com/russross/blackfriday
+//
+// Copyright © 2011 Russ Ross <russ@russross.com>.
+// Distributed under the Simplified BSD License.
+// See README.md for details.
+//
+
+//
+// Functions to parse block-level elements.
+//
+
+package blackfriday
+
+import (
+	"bytes"
+	"unicode"
+)
+
+// Parse block-level data.
+// Note: this function and many that it calls assume that
+// the input buffer ends with a newline.
+func (p *parser) block(out *bytes.Buffer, data []byte) {
+	if len(data) == 0 || data[len(data)-1] != '\n' {
+		panic("block input is missing terminating newline")
+	}
+
+	// this is called recursively: enforce a maximum depth
+	if p.nesting >= p.maxNesting {
+		return
+	}
+	p.nesting++
+
+	// parse out one block-level construct at a time
+	for len(data) > 0 {
+		// prefixed header:
+		//
+		// # Header 1
+		// ## Header 2
+		// ...
+		// ###### Header 6
+		if p.isPrefixHeader(data) {
+			data = data[p.prefixHeader(out, data):]
+			continue
+		}
+
+		// block of preformatted HTML:
+		//
+		// <div>
+		//     ...
+		// </div>
+		if data[0] == '<' {
+			if i := p.html(out, data, true); i > 0 {
+				data = data[i:]
+				continue
+			}
+		}
+
+		// title block
+		//
+		// % stuff
+		// % more stuff
+		// % even more stuff
+		if p.flags&EXTENSION_TITLEBLOCK != 0 {
+			if data[0] == '%' {
+				if i := p.titleBlock(out, data, true); i > 0 {
+					data = data[i:]
+					continue
+				}
+			}
+		}
+
+		// blank lines.  note: returns the # of bytes to skip
+		if i := p.isEmpty(data); i > 0 {
+			data = data[i:]
+			continue
+		}
+
+		// indented code block:
+		//
+		//     func max(a, b int) int {
+		//         if a > b {
+		//             return a
+		//         }
+		//         return b
+		//      }
+		if p.codePrefix(data) > 0 {
+			data = data[p.code(out, data):]
+			continue
+		}
+
+		// fenced code block:
+		//
+		// ``` go
+		// func fact(n int) int {
+		//     if n <= 1 {
+		//         return n
+		//     }
+		//     return n * fact(n-1)
+		// }
+		// ```
+		if p.flags&EXTENSION_FENCED_CODE != 0 {
+			if i := p.fencedCodeBlock(out, data, true); i > 0 {
+				data = data[i:]
+				continue
+			}
+		}
+
+		// horizontal rule:
+		//
+		// ------
+		// or
+		// ******
+		// or
+		// ______
+		if p.isHRule(data) {
+			p.r.HRule(out)
+			var i int
+			for i = 0; data[i] != '\n'; i++ {
+			}
+			data = data[i:]
+			continue
+		}
+
+		// block quote:
+		//
+		// > A big quote I found somewhere
+		// > on the web
+		if p.quotePrefix(data) > 0 {
+			data = data[p.quote(out, data):]
+			continue
+		}
+
+		// table:
+		//
+		// Name  | Age | Phone
+		// ------|-----|---------
+		// Bob   | 31  | 555-1234
+		// Alice | 27  | 555-4321
+		if p.flags&EXTENSION_TABLES != 0 {
+			if i := p.table(out, data); i > 0 {
+				data = data[i:]
+				continue
+			}
+		}
+
+		// an itemized/unordered list:
+		//
+		// * Item 1
+		// * Item 2
+		//
+		// also works with + or -
+		if p.uliPrefix(data) > 0 {
+			data = data[p.list(out, data, 0):]
+			continue
+		}
+
+		// a numbered/ordered list:
+		//
+		// 1. Item 1
+		// 2. Item 2
+		if p.oliPrefix(data) > 0 {
+			data = data[p.list(out, data, LIST_TYPE_ORDERED):]
+			continue
+		}
+
+		// definition lists:
+		//
+		// Term 1
+		// :   Definition a
+		// :   Definition b
+		//
+		// Term 2
+		// :   Definition c
+		if p.flags&EXTENSION_DEFINITION_LISTS != 0 {
+			if p.dliPrefix(data) > 0 {
+				data = data[p.list(out, data, LIST_TYPE_DEFINITION):]
+				continue
+			}
+		}
+
+		// anything else must look like a normal paragraph
+		// note: this finds underlined headers, too
+		data = data[p.paragraph(out, data):]
+	}
+
+	p.nesting--
+}
+
+func (p *parser) isPrefixHeader(data []byte) bool {
+	if data[0] != '#' {
+		return false
+	}
+
+	if p.flags&EXTENSION_SPACE_HEADERS != 0 {
+		level := 0
+		for level < 6 && data[level] == '#' {
+			level++
+		}
+		if data[level] != ' ' {
+			return false
+		}
+	}
+	return true
+}
+
+func (p *parser) prefixHeader(out *bytes.Buffer, data []byte) int {
+	level := 0
+	for level < 6 && data[level] == '#' {
+		level++
+	}
+	i := skipChar(data, level, ' ')
+	end := skipUntilChar(data, i, '\n')
+	skip := end
+	id := ""
+	if p.flags&EXTENSION_HEADER_IDS != 0 {
+		j, k := 0, 0
+		// find start/end of header id
+		for j = i; j < end-1 && (data[j] != '{' || data[j+1] != '#'); j++ {
+		}
+		for k = j + 1; k < end && data[k] != '}'; k++ {
+		}
+		// extract header id iff found
+		if j < end && k < end {
+			id = string(data[j+2 : k])
+			end = j
+			skip = k + 1
+			for end > 0 && data[end-1] == ' ' {
+				end--
+			}
+		}
+	}
+	for end > 0 && data[end-1] == '#' {
+		if isBackslashEscaped(data, end-1) {
+			break
+		}
+		end--
+	}
+	for end > 0 && data[end-1] == ' ' {
+		end--
+	}
+	if end > i {
+		if id == "" && p.flags&EXTENSION_AUTO_HEADER_IDS != 0 {
+			id = SanitizedAnchorName(string(data[i:end]))
+		}
+		work := func() bool {
+			p.inline(out, data[i:end])
+			return true
+		}
+		p.r.Header(out, work, level, id)
+	}
+	return skip
+}
+
+func (p *parser) isUnderlinedHeader(data []byte) int {
+	// test of level 1 header
+	if data[0] == '=' {
+		i := skipChar(data, 1, '=')
+		i = skipChar(data, i, ' ')
+		if data[i] == '\n' {
+			return 1
+		} else {
+			return 0
+		}
+	}
+
+	// test of level 2 header
+	if data[0] == '-' {
+		i := skipChar(data, 1, '-')
+		i = skipChar(data, i, ' ')
+		if data[i] == '\n' {
+			return 2
+		} else {
+			return 0
+		}
+	}
+
+	return 0
+}
+
+func (p *parser) titleBlock(out *bytes.Buffer, data []byte, doRender bool) int {
+	if data[0] != '%' {
+		return 0
+	}
+	splitData := bytes.Split(data, []byte("\n"))
+	var i int
+	for idx, b := range splitData {
+		if !bytes.HasPrefix(b, []byte("%")) {
+			i = idx // - 1
+			break
+		}
+	}
+
+	data = bytes.Join(splitData[0:i], []byte("\n"))
+	p.r.TitleBlock(out, data)
+
+	return len(data)
+}
+
+func (p *parser) html(out *bytes.Buffer, data []byte, doRender bool) int {
+	var i, j int
+
+	// identify the opening tag
+	if data[0] != '<' {
+		return 0
+	}
+	curtag, tagfound := p.htmlFindTag(data[1:])
+
+	// handle special cases
+	if !tagfound {
+		// check for an HTML comment
+		if size := p.htmlComment(out, data, doRender); size > 0 {
+			return size
+		}
+
+		// check for an <hr> tag
+		if size := p.htmlHr(out, data, doRender); size > 0 {
+			return size
+		}
+
+		// check for HTML CDATA
+		if size := p.htmlCDATA(out, data, doRender); size > 0 {
+			return size
+		}
+
+		// no special case recognized
+		return 0
+	}
+
+	// look for an unindented matching closing tag
+	// followed by a blank line
+	found := false
+	/*
+		closetag := []byte("\n</" + curtag + ">")
+		j = len(curtag) + 1
+		for !found {
+			// scan for a closing tag at the beginning of a line
+			if skip := bytes.Index(data[j:], closetag); skip >= 0 {
+				j += skip + len(closetag)
+			} else {
+				break
+			}
+
+			// see if it is the only thing on the line
+			if skip := p.isEmpty(data[j:]); skip > 0 {
+				// see if it is followed by a blank line/eof
+				j += skip
+				if j >= len(data) {
+					found = true
+					i = j
+				} else {
+					if skip := p.isEmpty(data[j:]); skip > 0 {
+						j += skip
+						found = true
+						i = j
+					}
+				}
+			}
+		}
+	*/
+
+	// if not found, try a second pass looking for indented match
+	// but not if tag is "ins" or "del" (following original Markdown.pl)
+	if !found && curtag != "ins" && curtag != "del" {
+		i = 1
+		for i < len(data) {
+			i++
+			for i < len(data) && !(data[i-1] == '<' && data[i] == '/') {
+				i++
+			}
+
+			if i+2+len(curtag) >= len(data) {
+				break
+			}
+
+			j = p.htmlFindEnd(curtag, data[i-1:])
+
+			if j > 0 {
+				i += j - 1
+				found = true
+				break
+			}
+		}
+	}
+
+	if !found {
+		return 0
+	}
+
+	// the end of the block has been found
+	if doRender {
+		// trim newlines
+		end := i
+		for end > 0 && data[end-1] == '\n' {
+			end--
+		}
+		p.r.BlockHtml(out, data[:end])
+	}
+
+	return i
+}
+
+func (p *parser) renderHTMLBlock(out *bytes.Buffer, data []byte, start int, doRender bool) int {
+	// html block needs to end with a blank line
+	if i := p.isEmpty(data[start:]); i > 0 {
+		size := start + i
+		if doRender {
+			// trim trailing newlines
+			end := size
+			for end > 0 && data[end-1] == '\n' {
+				end--
+			}
+			p.r.BlockHtml(out, data[:end])
+		}
+		return size
+	}
+	return 0
+}
+
+// HTML comment, lax form
+func (p *parser) htmlComment(out *bytes.Buffer, data []byte, doRender bool) int {
+	i := p.inlineHTMLComment(out, data)
+	return p.renderHTMLBlock(out, data, i, doRender)
+}
+
+// HTML CDATA section
+func (p *parser) htmlCDATA(out *bytes.Buffer, data []byte, doRender bool) int {
+	const cdataTag = "<![cdata["
+	const cdataTagLen = len(cdataTag)
+	if len(data) < cdataTagLen+1 {
+		return 0
+	}
+	if !bytes.Equal(bytes.ToLower(data[:cdataTagLen]), []byte(cdataTag)) {
+		return 0
+	}
+	i := cdataTagLen
+	// scan for an end-of-comment marker, across lines if necessary
+	for i < len(data) && !(data[i-2] == ']' && data[i-1] == ']' && data[i] == '>') {
+		i++
+	}
+	i++
+	// no end-of-comment marker
+	if i >= len(data) {
+		return 0
+	}
+	return p.renderHTMLBlock(out, data, i, doRender)
+}
+
+// HR, which is the only self-closing block tag considered
+func (p *parser) htmlHr(out *bytes.Buffer, data []byte, doRender bool) int {
+	if data[0] != '<' || (data[1] != 'h' && data[1] != 'H') || (data[2] != 'r' && data[2] != 'R') {
+		return 0
+	}
+	if data[3] != ' ' && data[3] != '/' && data[3] != '>' {
+		// not an <hr> tag after all; at least not a valid one
+		return 0
+	}
+
+	i := 3
+	for data[i] != '>' && data[i] != '\n' {
+		i++
+	}
+
+	if data[i] == '>' {
+		return p.renderHTMLBlock(out, data, i+1, doRender)
+	}
+
+	return 0
+}
+
+func (p *parser) htmlFindTag(data []byte) (string, bool) {
+	i := 0
+	for isalnum(data[i]) {
+		i++
+	}
+	key := string(data[:i])
+	if _, ok := blockTags[key]; ok {
+		return key, true
+	}
+	return "", false
+}
+
+func (p *parser) htmlFindEnd(tag string, data []byte) int {
+	// assume data[0] == '<' && data[1] == '/' already tested
+
+	// check if tag is a match
+	closetag := []byte("</" + tag + ">")
+	if !bytes.HasPrefix(data, closetag) {
+		return 0
+	}
+	i := len(closetag)
+
+	// check that the rest of the line is blank
+	skip := 0
+	if skip = p.isEmpty(data[i:]); skip == 0 {
+		return 0
+	}
+	i += skip
+	skip = 0
+
+	if i >= len(data) {
+		return i
+	}
+
+	if p.flags&EXTENSION_LAX_HTML_BLOCKS != 0 {
+		return i
+	}
+	if skip = p.isEmpty(data[i:]); skip == 0 {
+		// following line must be blank
+		return 0
+	}
+
+	return i + skip
+}
+
+func (*parser) isEmpty(data []byte) int {
+	// it is okay to call isEmpty on an empty buffer
+	if len(data) == 0 {
+		return 0
+	}
+
+	var i int
+	for i = 0; i < len(data) && data[i] != '\n'; i++ {
+		if data[i] != ' ' && data[i] != '\t' {
+			return 0
+		}
+	}
+	return i + 1
+}
+
+func (*parser) isHRule(data []byte) bool {
+	i := 0
+
+	// skip up to three spaces
+	for i < 3 && data[i] == ' ' {
+		i++
+	}
+
+	// look at the hrule char
+	if data[i] != '*' && data[i] != '-' && data[i] != '_' {
+		return false
+	}
+	c := data[i]
+
+	// the whole line must be the char or whitespace
+	n := 0
+	for data[i] != '\n' {
+		switch {
+		case data[i] == c:
+			n++
+		case data[i] != ' ':
+			return false
+		}
+		i++
+	}
+
+	return n >= 3
+}
+
+// isFenceLine checks if there's a fence line (e.g., ``` or ``` go) at the beginning of data,
+// and returns the end index if so, or 0 otherwise. It also returns the marker found.
+// If syntax is not nil, it gets set to the syntax specified in the fence line.
+// A final newline is mandatory to recognize the fence line, unless newlineOptional is true.
+func isFenceLine(data []byte, syntax *string, oldmarker string, newlineOptional bool) (end int, marker string) {
+	i, size := 0, 0
+
+	// skip up to three spaces
+	for i < len(data) && i < 3 && data[i] == ' ' {
+		i++
+	}
+
+	// check for the marker characters: ~ or `
+	if i >= len(data) {
+		return 0, ""
+	}
+	if data[i] != '~' && data[i] != '`' {
+		return 0, ""
+	}
+
+	c := data[i]
+
+	// the whole line must be the same char or whitespace
+	for i < len(data) && data[i] == c {
+		size++
+		i++
+	}
+
+	// the marker char must occur at least 3 times
+	if size < 3 {
+		return 0, ""
+	}
+	marker = string(data[i-size : i])
+
+	// if this is the end marker, it must match the beginning marker
+	if oldmarker != "" && marker != oldmarker {
+		return 0, ""
+	}
+
+	// TODO(shurcooL): It's probably a good idea to simplify the 2 code paths here
+	// into one, always get the syntax, and discard it if the caller doesn't care.
+	if syntax != nil {
+		syn := 0
+		i = skipChar(data, i, ' ')
+
+		if i >= len(data) {
+			if newlineOptional && i == len(data) {
+				return i, marker
+			}
+			return 0, ""
+		}
+
+		syntaxStart := i
+
+		if data[i] == '{' {
+			i++
+			syntaxStart++
+
+			for i < len(data) && data[i] != '}' && data[i] != '\n' {
+				syn++
+				i++
+			}
+
+			if i >= len(data) || data[i] != '}' {
+				return 0, ""
+			}
+
+			// strip all whitespace at the beginning and the end
+			// of the {} block
+			for syn > 0 && isspace(data[syntaxStart]) {
+				syntaxStart++
+				syn--
+			}
+
+			for syn > 0 && isspace(data[syntaxStart+syn-1]) {
+				syn--
+			}
+
+			i++
+		} else {
+			for i < len(data) && !isspace(data[i]) {
+				syn++
+				i++
+			}
+		}
+
+		*syntax = string(data[syntaxStart : syntaxStart+syn])
+	}
+
+	i = skipChar(data, i, ' ')
+	if i >= len(data) || data[i] != '\n' {
+		if newlineOptional && i == len(data) {
+			return i, marker
+		}
+		return 0, ""
+	}
+
+	return i + 1, marker // Take newline into account.
+}
+
+// fencedCodeBlock returns the end index if data contains a fenced code block at the beginning,
+// or 0 otherwise. It writes to out if doRender is true, otherwise it has no side effects.
+// If doRender is true, a final newline is mandatory to recognize the fenced code block.
+func (p *parser) fencedCodeBlock(out *bytes.Buffer, data []byte, doRender bool) int {
+	var syntax string
+	beg, marker := isFenceLine(data, &syntax, "", false)
+	if beg == 0 || beg >= len(data) {
+		return 0
+	}
+
+	var work bytes.Buffer
+
+	for {
+		// safe to assume beg < len(data)
+
+		// check for the end of the code block
+		newlineOptional := !doRender
+		fenceEnd, _ := isFenceLine(data[beg:], nil, marker, newlineOptional)
+		if fenceEnd != 0 {
+			beg += fenceEnd
+			break
+		}
+
+		// copy the current line
+		end := skipUntilChar(data, beg, '\n') + 1
+
+		// did we reach the end of the buffer without a closing marker?
+		if end >= len(data) {
+			return 0
+		}
+
+		// verbatim copy to the working buffer
+		if doRender {
+			work.Write(data[beg:end])
+		}
+		beg = end
+	}
+
+	if doRender {
+		p.r.BlockCode(out, work.Bytes(), syntax)
+	}
+
+	return beg
+}
+
+func (p *parser) table(out *bytes.Buffer, data []byte) int {
+	var header bytes.Buffer
+	i, columns := p.tableHeader(&header, data)
+	if i == 0 {
+		return 0
+	}
+
+	var body bytes.Buffer
+
+	for i < len(data) {
+		pipes, rowStart := 0, i
+		for ; data[i] != '\n'; i++ {
+			if data[i] == '|' {
+				pipes++
+			}
+		}
+
+		if pipes == 0 {
+			i = rowStart
+			break
+		}
+
+		// include the newline in data sent to tableRow
+		i++
+		p.tableRow(&body, data[rowStart:i], columns, false)
+	}
+
+	p.r.Table(out, header.Bytes(), body.Bytes(), columns)
+
+	return i
+}
+
+// check if the specified position is preceded by an odd number of backslashes
+func isBackslashEscaped(data []byte, i int) bool {
+	backslashes := 0
+	for i-backslashes-1 >= 0 && data[i-backslashes-1] == '\\' {
+		backslashes++
+	}
+	return backslashes&1 == 1
+}
+
+func (p *parser) tableHeader(out *bytes.Buffer, data []byte) (size int, columns []int) {
+	i := 0
+	colCount := 1
+	for i = 0; data[i] != '\n'; i++ {
+		if data[i] == '|' && !isBackslashEscaped(data, i) {
+			colCount++
+		}
+	}
+
+	// doesn't look like a table header
+	if colCount == 1 {
+		return
+	}
+
+	// include the newline in the data sent to tableRow
+	header := data[:i+1]
+
+	// column count ignores pipes at beginning or end of line
+	if data[0] == '|' {
+		colCount--
+	}
+	if i > 2 && data[i-1] == '|' && !isBackslashEscaped(data, i-1) {
+		colCount--
+	}
+
+	columns = make([]int, colCount)
+
+	// move on to the header underline
+	i++
+	if i >= len(data) {
+		return
+	}
+
+	if data[i] == '|' && !isBackslashEscaped(data, i) {
+		i++
+	}
+	i = skipChar(data, i, ' ')
+
+	// each column header is of form: / *:?-+:? *|/ with # dashes + # colons >= 3
+	// and trailing | optional on last column
+	col := 0
+	for data[i] != '\n' {
+		dashes := 0
+
+		if data[i] == ':' {
+			i++
+			columns[col] |= TABLE_ALIGNMENT_LEFT
+			dashes++
+		}
+		for data[i] == '-' {
+			i++
+			dashes++
+		}
+		if data[i] == ':' {
+			i++
+			columns[col] |= TABLE_ALIGNMENT_RIGHT
+			dashes++
+		}
+		for data[i] == ' ' {
+			i++
+		}
+
+		// end of column test is messy
+		switch {
+		case dashes < 3:
+			// not a valid column
+			return
+
+		case data[i] == '|' && !isBackslashEscaped(data, i):
+			// marker found, now skip past trailing whitespace
+			col++
+			i++
+			for data[i] == ' ' {
+				i++
+			}
+
+			// trailing junk found after last column
+			if col >= colCount && data[i] != '\n' {
+				return
+			}
+
+		case (data[i] != '|' || isBackslashEscaped(data, i)) && col+1 < colCount:
+			// something else found where marker was required
+			return
+
+		case data[i] == '\n':
+			// marker is optional for the last column
+			col++
+
+		default:
+			// trailing junk found after last column
+			return
+		}
+	}
+	if col != colCount {
+		return
+	}
+
+	p.tableRow(out, header, columns, true)
+	size = i + 1
+	return
+}
+
+func (p *parser) tableRow(out *bytes.Buffer, data []byte, columns []int, header bool) {
+	i, col := 0, 0
+	var rowWork bytes.Buffer
+
+	if data[i] == '|' && !isBackslashEscaped(data, i) {
+		i++
+	}
+
+	for col = 0; col < len(columns) && i < len(data); col++ {
+		for data[i] == ' ' {
+			i++
+		}
+
+		cellStart := i
+
+		for (data[i] != '|' || isBackslashEscaped(data, i)) && data[i] != '\n' {
+			i++
+		}
+
+		cellEnd := i
+
+		// skip the end-of-cell marker, possibly taking us past end of buffer
+		i++
+
+		for cellEnd > cellStart && data[cellEnd-1] == ' ' {
+			cellEnd--
+		}
+
+		var cellWork bytes.Buffer
+		p.inline(&cellWork, data[cellStart:cellEnd])
+
+		if header {
+			p.r.TableHeaderCell(&rowWork, cellWork.Bytes(), columns[col])
+		} else {
+			p.r.TableCell(&rowWork, cellWork.Bytes(), columns[col])
+		}
+	}
+
+	// pad it out with empty columns to get the right number
+	for ; col < len(columns); col++ {
+		if header {
+			p.r.TableHeaderCell(&rowWork, nil, columns[col])
+		} else {
+			p.r.TableCell(&rowWork, nil, columns[col])
+		}
+	}
+
+	// silently ignore rows with too many cells
+
+	p.r.TableRow(out, rowWork.Bytes())
+}
+
+// returns blockquote prefix length
+func (p *parser) quotePrefix(data []byte) int {
+	i := 0
+	for i < 3 && data[i] == ' ' {
+		i++
+	}
+	if data[i] == '>' {
+		if data[i+1] == ' ' {
+			return i + 2
+		}
+		return i + 1
+	}
+	return 0
+}
+
+// blockquote ends with at least one blank line
+// followed by something without a blockquote prefix
+func (p *parser) terminateBlockquote(data []byte, beg, end int) bool {
+	if p.isEmpty(data[beg:]) <= 0 {
+		return false
+	}
+	if end >= len(data) {
+		return true
+	}
+	return p.quotePrefix(data[end:]) == 0 && p.isEmpty(data[end:]) == 0
+}
+
+// parse a blockquote fragment
+func (p *parser) quote(out *bytes.Buffer, data []byte) int {
+	var raw bytes.Buffer
+	beg, end := 0, 0
+	for beg < len(data) {
+		end = beg
+		// Step over whole lines, collecting them. While doing that, check for
+		// fenced code and if one's found, incorporate it altogether,
+		// irregardless of any contents inside it
+		for data[end] != '\n' {
+			if p.flags&EXTENSION_FENCED_CODE != 0 {
+				if i := p.fencedCodeBlock(out, data[end:], false); i > 0 {
+					// -1 to compensate for the extra end++ after the loop:
+					end += i - 1
+					break
+				}
+			}
+			end++
+		}
+		end++
+
+		if pre := p.quotePrefix(data[beg:]); pre > 0 {
+			// skip the prefix
+			beg += pre
+		} else if p.terminateBlockquote(data, beg, end) {
+			break
+		}
+
+		// this line is part of the blockquote
+		raw.Write(data[beg:end])
+		beg = end
+	}
+
+	var cooked bytes.Buffer
+	p.block(&cooked, raw.Bytes())
+	p.r.BlockQuote(out, cooked.Bytes())
+	return end
+}
+
+// returns prefix length for block code
+func (p *parser) codePrefix(data []byte) int {
+	if data[0] == ' ' && data[1] == ' ' && data[2] == ' ' && data[3] == ' ' {
+		return 4
+	}
+	return 0
+}
+
+func (p *parser) code(out *bytes.Buffer, data []byte) int {
+	var work bytes.Buffer
+
+	i := 0
+	for i < len(data) {
+		beg := i
+		for data[i] != '\n' {
+			i++
+		}
+		i++
+
+		blankline := p.isEmpty(data[beg:i]) > 0
+		if pre := p.codePrefix(data[beg:i]); pre > 0 {
+			beg += pre
+		} else if !blankline {
+			// non-empty, non-prefixed line breaks the pre
+			i = beg
+			break
+		}
+
+		// verbatim copy to the working buffeu
+		if blankline {
+			work.WriteByte('\n')
+		} else {
+			work.Write(data[beg:i])
+		}
+	}
+
+	// trim all the \n off the end of work
+	workbytes := work.Bytes()
+	eol := len(workbytes)
+	for eol > 0 && workbytes[eol-1] == '\n' {
+		eol--
+	}
+	if eol != len(workbytes) {
+		work.Truncate(eol)
+	}
+
+	work.WriteByte('\n')
+
+	p.r.BlockCode(out, work.Bytes(), "")
+
+	return i
+}
+
+// returns unordered list item prefix
+func (p *parser) uliPrefix(data []byte) int {
+	i := 0
+
+	// start with up to 3 spaces
+	for i < 3 && data[i] == ' ' {
+		i++
+	}
+
+	// need a *, +, or - followed by a space
+	if (data[i] != '*' && data[i] != '+' && data[i] != '-') ||
+		data[i+1] != ' ' {
+		return 0
+	}
+	return i + 2
+}
+
+// returns ordered list item prefix
+func (p *parser) oliPrefix(data []byte) int {
+	i := 0
+
+	// start with up to 3 spaces
+	for i < 3 && data[i] == ' ' {
+		i++
+	}
+
+	// count the digits
+	start := i
+	for data[i] >= '0' && data[i] <= '9' {
+		i++
+	}
+
+	// we need >= 1 digits followed by a dot and a space
+	if start == i || data[i] != '.' || data[i+1] != ' ' {
+		return 0
+	}
+	return i + 2
+}
+
+// returns definition list item prefix
+func (p *parser) dliPrefix(data []byte) int {
+	i := 0
+
+	// need a : followed by a spaces
+	if data[i] != ':' || data[i+1] != ' ' {
+		return 0
+	}
+	for data[i] == ' ' {
+		i++
+	}
+	return i + 2
+}
+
+// parse ordered or unordered list block
+func (p *parser) list(out *bytes.Buffer, data []byte, flags int) int {
+	i := 0
+	flags |= LIST_ITEM_BEGINNING_OF_LIST
+	work := func() bool {
+		for i < len(data) {
+			skip := p.listItem(out, data[i:], &flags)
+			i += skip
+
+			if skip == 0 || flags&LIST_ITEM_END_OF_LIST != 0 {
+				break
+			}
+			flags &= ^LIST_ITEM_BEGINNING_OF_LIST
+		}
+		return true
+	}
+
+	p.r.List(out, work, flags)
+	return i
+}
+
+// Parse a single list item.
+// Assumes initial prefix is already removed if this is a sublist.
+func (p *parser) listItem(out *bytes.Buffer, data []byte, flags *int) int {
+	// keep track of the indentation of the first line
+	itemIndent := 0
+	for itemIndent < 3 && data[itemIndent] == ' ' {
+		itemIndent++
+	}
+
+	i := p.uliPrefix(data)
+	if i == 0 {
+		i = p.oliPrefix(data)
+	}
+	if i == 0 {
+		i = p.dliPrefix(data)
+		// reset definition term flag
+		if i > 0 {
+			*flags &= ^LIST_TYPE_TERM
+		}
+	}
+	if i == 0 {
+		// if in defnition list, set term flag and continue
+		if *flags&LIST_TYPE_DEFINITION != 0 {
+			*flags |= LIST_TYPE_TERM
+		} else {
+			return 0
+		}
+	}
+
+	// skip leading whitespace on first line
+	for data[i] == ' ' {
+		i++
+	}
+
+	// find the end of the line
+	line := i
+	for i > 0 && data[i-1] != '\n' {
+		i++
+	}
+
+	// get working buffer
+	var raw bytes.Buffer
+
+	// put the first line into the working buffer
+	raw.Write(data[line:i])
+	line = i
+
+	// process the following lines
+	containsBlankLine := false
+	sublist := 0
+
+gatherlines:
+	for line < len(data) {
+		i++
+
+		// find the end of this line
+		for data[i-1] != '\n' {
+			i++
+		}
+
+		// if it is an empty line, guess that it is part of this item
+		// and move on to the next line
+		if p.isEmpty(data[line:i]) > 0 {
+			containsBlankLine = true
+			raw.Write(data[line:i])
+			line = i
+			continue
+		}
+
+		// calculate the indentation
+		indent := 0
+		for indent < 4 && line+indent < i && data[line+indent] == ' ' {
+			indent++
+		}
+
+		chunk := data[line+indent : i]
+
+		// evaluate how this line fits in
+		switch {
+		// is this a nested list item?
+		case (p.uliPrefix(chunk) > 0 && !p.isHRule(chunk)) ||
+			p.oliPrefix(chunk) > 0 ||
+			p.dliPrefix(chunk) > 0:
+
+			if containsBlankLine {
+				// end the list if the type changed after a blank line
+				if indent <= itemIndent &&
+					((*flags&LIST_TYPE_ORDERED != 0 && p.uliPrefix(chunk) > 0) ||
+						(*flags&LIST_TYPE_ORDERED == 0 && p.oliPrefix(chunk) > 0)) {
+
+					*flags |= LIST_ITEM_END_OF_LIST
+					break gatherlines
+				}
+				*flags |= LIST_ITEM_CONTAINS_BLOCK
+			}
+
+			// to be a nested list, it must be indented more
+			// if not, it is the next item in the same list
+			if indent <= itemIndent {
+				break gatherlines
+			}
+
+			// is this the first item in the nested list?
+			if sublist == 0 {
+				sublist = raw.Len()
+			}
+
+		// is this a nested prefix header?
+		case p.isPrefixHeader(chunk):
+			// if the header is not indented, it is not nested in the list
+			// and thus ends the list
+			if containsBlankLine && indent < 4 {
+				*flags |= LIST_ITEM_END_OF_LIST
+				break gatherlines
+			}
+			*flags |= LIST_ITEM_CONTAINS_BLOCK
+
+		// anything following an empty line is only part
+		// of this item if it is indented 4 spaces
+		// (regardless of the indentation of the beginning of the item)
+		case containsBlankLine && indent < 4:
+			if *flags&LIST_TYPE_DEFINITION != 0 && i < len(data)-1 {
+				// is the next item still a part of this list?
+				next := i
+				for data[next] != '\n' {
+					next++
+				}
+				for next < len(data)-1 && data[next] == '\n' {
+					next++
+				}
+				if i < len(data)-1 && data[i] != ':' && data[next] != ':' {
+					*flags |= LIST_ITEM_END_OF_LIST
+				}
+			} else {
+				*flags |= LIST_ITEM_END_OF_LIST
+			}
+			break gatherlines
+
+		// a blank line means this should be parsed as a block
+		case containsBlankLine:
+			*flags |= LIST_ITEM_CONTAINS_BLOCK
+		}
+
+		containsBlankLine = false
+
+		// add the line into the working buffer without prefix
+		raw.Write(data[line+indent : i])
+
+		line = i
+	}
+
+	// If reached end of data, the Renderer.ListItem call we're going to make below
+	// is definitely the last in the list.
+	if line >= len(data) {
+		*flags |= LIST_ITEM_END_OF_LIST
+	}
+
+	rawBytes := raw.Bytes()
+
+	// render the contents of the list item
+	var cooked bytes.Buffer
+	if *flags&LIST_ITEM_CONTAINS_BLOCK != 0 && *flags&LIST_TYPE_TERM == 0 {
+		// intermediate render of block item, except for definition term
+		if sublist > 0 {
+			p.block(&cooked, rawBytes[:sublist])
+			p.block(&cooked, rawBytes[sublist:])
+		} else {
+			p.block(&cooked, rawBytes)
+		}
+	} else {
+		// intermediate render of inline item
+		if sublist > 0 {
+			p.inline(&cooked, rawBytes[:sublist])
+			p.block(&cooked, rawBytes[sublist:])
+		} else {
+			p.inline(&cooked, rawBytes)
+		}
+	}
+
+	// render the actual list item
+	cookedBytes := cooked.Bytes()
+	parsedEnd := len(cookedBytes)
+
+	// strip trailing newlines
+	for parsedEnd > 0 && cookedBytes[parsedEnd-1] == '\n' {
+		parsedEnd--
+	}
+	p.r.ListItem(out, cookedBytes[:parsedEnd], *flags)
+
+	return line
+}
+
+// render a single paragraph that has already been parsed out
+func (p *parser) renderParagraph(out *bytes.Buffer, data []byte) {
+	if len(data) == 0 {
+		return
+	}
+
+	// trim leading spaces
+	beg := 0
+	for data[beg] == ' ' {
+		beg++
+	}
+
+	// trim trailing newline
+	end := len(data) - 1
+
+	// trim trailing spaces
+	for end > beg && data[end-1] == ' ' {
+		end--
+	}
+
+	work := func() bool {
+		p.inline(out, data[beg:end])
+		return true
+	}
+	p.r.Paragraph(out, work)
+}
+
+func (p *parser) paragraph(out *bytes.Buffer, data []byte) int {
+	// prev: index of 1st char of previous line
+	// line: index of 1st char of current line
+	// i: index of cursor/end of current line
+	var prev, line, i int
+
+	// keep going until we find something to mark the end of the paragraph
+	for i < len(data) {
+		// mark the beginning of the current line
+		prev = line
+		current := data[i:]
+		line = i
+
+		// did we find a blank line marking the end of the paragraph?
+		if n := p.isEmpty(current); n > 0 {
+			// did this blank line followed by a definition list item?
+			if p.flags&EXTENSION_DEFINITION_LISTS != 0 {
+				if i < len(data)-1 && data[i+1] == ':' {
+					return p.list(out, data[prev:], LIST_TYPE_DEFINITION)
+				}
+			}
+
+			p.renderParagraph(out, data[:i])
+			return i + n
+		}
+
+		// an underline under some text marks a header, so our paragraph ended on prev line
+		if i > 0 {
+			if level := p.isUnderlinedHeader(current); level > 0 {
+				// render the paragraph
+				p.renderParagraph(out, data[:prev])
+
+				// ignore leading and trailing whitespace
+				eol := i - 1
+				for prev < eol && data[prev] == ' ' {
+					prev++
+				}
+				for eol > prev && data[eol-1] == ' ' {
+					eol--
+				}
+
+				// render the header
+				// this ugly double closure avoids forcing variables onto the heap
+				work := func(o *bytes.Buffer, pp *parser, d []byte) func() bool {
+					return func() bool {
+						pp.inline(o, d)
+						return true
+					}
+				}(out, p, data[prev:eol])
+
+				id := ""
+				if p.flags&EXTENSION_AUTO_HEADER_IDS != 0 {
+					id = SanitizedAnchorName(string(data[prev:eol]))
+				}
+
+				p.r.Header(out, work, level, id)
+
+				// find the end of the underline
+				for data[i] != '\n' {
+					i++
+				}
+				return i
+			}
+		}
+
+		// if the next line starts a block of HTML, then the paragraph ends here
+		if p.flags&EXTENSION_LAX_HTML_BLOCKS != 0 {
+			if data[i] == '<' && p.html(out, current, false) > 0 {
+				// rewind to before the HTML block
+				p.renderParagraph(out, data[:i])
+				return i
+			}
+		}
+
+		// if there's a prefixed header or a horizontal rule after this, paragraph is over
+		if p.isPrefixHeader(current) || p.isHRule(current) {
+			p.renderParagraph(out, data[:i])
+			return i
+		}
+
+		// if there's a fenced code block, paragraph is over
+		if p.flags&EXTENSION_FENCED_CODE != 0 {
+			if p.fencedCodeBlock(out, current, false) > 0 {
+				p.renderParagraph(out, data[:i])
+				return i
+			}
+		}
+
+		// if there's a definition list item, prev line is a definition term
+		if p.flags&EXTENSION_DEFINITION_LISTS != 0 {
+			if p.dliPrefix(current) != 0 {
+				return p.list(out, data[prev:], LIST_TYPE_DEFINITION)
+			}
+		}
+
+		// if there's a list after this, paragraph is over
+		if p.flags&EXTENSION_NO_EMPTY_LINE_BEFORE_BLOCK != 0 {
+			if p.uliPrefix(current) != 0 ||
+				p.oliPrefix(current) != 0 ||
+				p.quotePrefix(current) != 0 ||
+				p.codePrefix(current) != 0 {
+				p.renderParagraph(out, data[:i])
+				return i
+			}
+		}
+
+		// otherwise, scan to the beginning of the next line
+		for data[i] != '\n' {
+			i++
+		}
+		i++
+	}
+
+	p.renderParagraph(out, data[:i])
+	return i
+}
+
+// SanitizedAnchorName returns a sanitized anchor name for the given text.
+//
+// It implements the algorithm specified in the package comment.
+func SanitizedAnchorName(text string) string {
+	var anchorName []rune
+	futureDash := false
+	for _, r := range text {
+		switch {
+		case unicode.IsLetter(r) || unicode.IsNumber(r):
+			if futureDash && len(anchorName) > 0 {
+				anchorName = append(anchorName, '-')
+			}
+			futureDash = false
+			anchorName = append(anchorName, unicode.ToLower(r))
+		default:
+			futureDash = true
+		}
+	}
+	return string(anchorName)
+}
diff --git a/vendor/github.com/russross/blackfriday/doc.go b/vendor/github.com/russross/blackfriday/doc.go
new file mode 100644
index 00000000..9656c42a
--- /dev/null
+++ b/vendor/github.com/russross/blackfriday/doc.go
@@ -0,0 +1,32 @@
+// Package blackfriday is a Markdown processor.
+//
+// It translates plain text with simple formatting rules into HTML or LaTeX.
+//
+// Sanitized Anchor Names
+//
+// Blackfriday includes an algorithm for creating sanitized anchor names
+// corresponding to a given input text. This algorithm is used to create
+// anchors for headings when EXTENSION_AUTO_HEADER_IDS is enabled. The
+// algorithm is specified below, so that other packages can create
+// compatible anchor names and links to those anchors.
+//
+// The algorithm iterates over the input text, interpreted as UTF-8,
+// one Unicode code point (rune) at a time. All runes that are letters (category L)
+// or numbers (category N) are considered valid characters. They are mapped to
+// lower case, and included in the output. All other runes are considered
+// invalid characters. Invalid characters that preceed the first valid character,
+// as well as invalid character that follow the last valid character
+// are dropped completely. All other sequences of invalid characters
+// between two valid characters are replaced with a single dash character '-'.
+//
+// SanitizedAnchorName exposes this functionality, and can be used to
+// create compatible links to the anchor names generated by blackfriday.
+// This algorithm is also implemented in a small standalone package at
+// github.com/shurcooL/sanitized_anchor_name. It can be useful for clients
+// that want a small package and don't need full functionality of blackfriday.
+package blackfriday
+
+// NOTE: Keep Sanitized Anchor Name algorithm in sync with package
+//       github.com/shurcooL/sanitized_anchor_name.
+//       Otherwise, users of sanitized_anchor_name will get anchor names
+//       that are incompatible with those generated by blackfriday.
diff --git a/vendor/github.com/russross/blackfriday/html.go b/vendor/github.com/russross/blackfriday/html.go
new file mode 100644
index 00000000..c917c7d3
--- /dev/null
+++ b/vendor/github.com/russross/blackfriday/html.go
@@ -0,0 +1,950 @@
+//
+// Blackfriday Markdown Processor
+// Available at http://github.com/russross/blackfriday
+//
+// Copyright © 2011 Russ Ross <russ@russross.com>.
+// Distributed under the Simplified BSD License.
+// See README.md for details.
+//
+
+//
+//
+// HTML rendering backend
+//
+//
+
+package blackfriday
+
+import (
+	"bytes"
+	"fmt"
+	"regexp"
+	"strconv"
+	"strings"
+)
+
+// Html renderer configuration options.
+const (
+	HTML_SKIP_HTML                 = 1 << iota // skip preformatted HTML blocks
+	HTML_SKIP_STYLE                            // skip embedded <style> elements
+	HTML_SKIP_IMAGES                           // skip embedded images
+	HTML_SKIP_LINKS                            // skip all links
+	HTML_SAFELINK                              // only link to trusted protocols
+	HTML_NOFOLLOW_LINKS                        // only link with rel="nofollow"
+	HTML_NOREFERRER_LINKS                      // only link with rel="noreferrer"
+	HTML_HREF_TARGET_BLANK                     // add a blank target
+	HTML_TOC                                   // generate a table of contents
+	HTML_OMIT_CONTENTS                         // skip the main contents (for a standalone table of contents)
+	HTML_COMPLETE_PAGE                         // generate a complete HTML page
+	HTML_USE_XHTML                             // generate XHTML output instead of HTML
+	HTML_USE_SMARTYPANTS                       // enable smart punctuation substitutions
+	HTML_SMARTYPANTS_FRACTIONS                 // enable smart fractions (with HTML_USE_SMARTYPANTS)
+	HTML_SMARTYPANTS_DASHES                    // enable smart dashes (with HTML_USE_SMARTYPANTS)
+	HTML_SMARTYPANTS_LATEX_DASHES              // enable LaTeX-style dashes (with HTML_USE_SMARTYPANTS and HTML_SMARTYPANTS_DASHES)
+	HTML_SMARTYPANTS_ANGLED_QUOTES             // enable angled double quotes (with HTML_USE_SMARTYPANTS) for double quotes rendering
+	HTML_SMARTYPANTS_QUOTES_NBSP               // enable "French guillemets" (with HTML_USE_SMARTYPANTS)
+	HTML_FOOTNOTE_RETURN_LINKS                 // generate a link at the end of a footnote to return to the source
+)
+
+var (
+	alignments = []string{
+		"left",
+		"right",
+		"center",
+	}
+
+	// TODO: improve this regexp to catch all possible entities:
+	htmlEntity = regexp.MustCompile(`&[a-z]{2,5};`)
+)
+
+type HtmlRendererParameters struct {
+	// Prepend this text to each relative URL.
+	AbsolutePrefix string
+	// Add this text to each footnote anchor, to ensure uniqueness.
+	FootnoteAnchorPrefix string
+	// Show this text inside the <a> tag for a footnote return link, if the
+	// HTML_FOOTNOTE_RETURN_LINKS flag is enabled. If blank, the string
+	// <sup>[return]</sup> is used.
+	FootnoteReturnLinkContents string
+	// If set, add this text to the front of each Header ID, to ensure
+	// uniqueness.
+	HeaderIDPrefix string
+	// If set, add this text to the back of each Header ID, to ensure uniqueness.
+	HeaderIDSuffix string
+}
+
+// Html is a type that implements the Renderer interface for HTML output.
+//
+// Do not create this directly, instead use the HtmlRenderer function.
+type Html struct {
+	flags    int    // HTML_* options
+	closeTag string // how to end singleton tags: either " />" or ">"
+	title    string // document title
+	css      string // optional css file url (used with HTML_COMPLETE_PAGE)
+
+	parameters HtmlRendererParameters
+
+	// table of contents data
+	tocMarker    int
+	headerCount  int
+	currentLevel int
+	toc          *bytes.Buffer
+
+	// Track header IDs to prevent ID collision in a single generation.
+	headerIDs map[string]int
+
+	smartypants *smartypantsRenderer
+}
+
+const (
+	xhtmlClose = " />"
+	htmlClose  = ">"
+)
+
+// HtmlRenderer creates and configures an Html object, which
+// satisfies the Renderer interface.
+//
+// flags is a set of HTML_* options ORed together.
+// title is the title of the document, and css is a URL for the document's
+// stylesheet.
+// title and css are only used when HTML_COMPLETE_PAGE is selected.
+func HtmlRenderer(flags int, title string, css string) Renderer {
+	return HtmlRendererWithParameters(flags, title, css, HtmlRendererParameters{})
+}
+
+func HtmlRendererWithParameters(flags int, title string,
+	css string, renderParameters HtmlRendererParameters) Renderer {
+	// configure the rendering engine
+	closeTag := htmlClose
+	if flags&HTML_USE_XHTML != 0 {
+		closeTag = xhtmlClose
+	}
+
+	if renderParameters.FootnoteReturnLinkContents == "" {
+		renderParameters.FootnoteReturnLinkContents = `<sup>[return]</sup>`
+	}
+
+	return &Html{
+		flags:      flags,
+		closeTag:   closeTag,
+		title:      title,
+		css:        css,
+		parameters: renderParameters,
+
+		headerCount:  0,
+		currentLevel: 0,
+		toc:          new(bytes.Buffer),
+
+		headerIDs: make(map[string]int),
+
+		smartypants: smartypants(flags),
+	}
+}
+
+// Using if statements is a bit faster than a switch statement. As the compiler
+// improves, this should be unnecessary this is only worthwhile because
+// attrEscape is the single largest CPU user in normal use.
+// Also tried using map, but that gave a ~3x slowdown.
+func escapeSingleChar(char byte) (string, bool) {
+	if char == '"' {
+		return "&quot;", true
+	}
+	if char == '&' {
+		return "&amp;", true
+	}
+	if char == '<' {
+		return "&lt;", true
+	}
+	if char == '>' {
+		return "&gt;", true
+	}
+	return "", false
+}
+
+func attrEscape(out *bytes.Buffer, src []byte) {
+	org := 0
+	for i, ch := range src {
+		if entity, ok := escapeSingleChar(ch); ok {
+			if i > org {
+				// copy all the normal characters since the last escape
+				out.Write(src[org:i])
+			}
+			org = i + 1
+			out.WriteString(entity)
+		}
+	}
+	if org < len(src) {
+		out.Write(src[org:])
+	}
+}
+
+func entityEscapeWithSkip(out *bytes.Buffer, src []byte, skipRanges [][]int) {
+	end := 0
+	for _, rang := range skipRanges {
+		attrEscape(out, src[end:rang[0]])
+		out.Write(src[rang[0]:rang[1]])
+		end = rang[1]
+	}
+	attrEscape(out, src[end:])
+}
+
+func (options *Html) GetFlags() int {
+	return options.flags
+}
+
+func (options *Html) TitleBlock(out *bytes.Buffer, text []byte) {
+	text = bytes.TrimPrefix(text, []byte("% "))
+	text = bytes.Replace(text, []byte("\n% "), []byte("\n"), -1)
+	out.WriteString("<h1 class=\"title\">")
+	out.Write(text)
+	out.WriteString("\n</h1>")
+}
+
+func (options *Html) Header(out *bytes.Buffer, text func() bool, level int, id string) {
+	marker := out.Len()
+	doubleSpace(out)
+
+	if id == "" && options.flags&HTML_TOC != 0 {
+		id = fmt.Sprintf("toc_%d", options.headerCount)
+	}
+
+	if id != "" {
+		id = options.ensureUniqueHeaderID(id)
+
+		if options.parameters.HeaderIDPrefix != "" {
+			id = options.parameters.HeaderIDPrefix + id
+		}
+
+		if options.parameters.HeaderIDSuffix != "" {
+			id = id + options.parameters.HeaderIDSuffix
+		}
+
+		out.WriteString(fmt.Sprintf("<h%d id=\"%s\">", level, id))
+	} else {
+		out.WriteString(fmt.Sprintf("<h%d>", level))
+	}
+
+	tocMarker := out.Len()
+	if !text() {
+		out.Truncate(marker)
+		return
+	}
+
+	// are we building a table of contents?
+	if options.flags&HTML_TOC != 0 {
+		options.TocHeaderWithAnchor(out.Bytes()[tocMarker:], level, id)
+	}
+
+	out.WriteString(fmt.Sprintf("</h%d>\n", level))
+}
+
+func (options *Html) BlockHtml(out *bytes.Buffer, text []byte) {
+	if options.flags&HTML_SKIP_HTML != 0 {
+		return
+	}
+
+	doubleSpace(out)
+	out.Write(text)
+	out.WriteByte('\n')
+}
+
+func (options *Html) HRule(out *bytes.Buffer) {
+	doubleSpace(out)
+	out.WriteString("<hr")
+	out.WriteString(options.closeTag)
+	out.WriteByte('\n')
+}
+
+func (options *Html) BlockCode(out *bytes.Buffer, text []byte, lang string) {
+	doubleSpace(out)
+
+	// parse out the language names/classes
+	count := 0
+	for _, elt := range strings.Fields(lang) {
+		if elt[0] == '.' {
+			elt = elt[1:]
+		}
+		if len(elt) == 0 {
+			continue
+		}
+		if count == 0 {
+			out.WriteString("<pre><code class=\"language-")
+		} else {
+			out.WriteByte(' ')
+		}
+		attrEscape(out, []byte(elt))
+		count++
+	}
+
+	if count == 0 {
+		out.WriteString("<pre><code>")
+	} else {
+		out.WriteString("\">")
+	}
+
+	attrEscape(out, text)
+	out.WriteString("</code></pre>\n")
+}
+
+func (options *Html) BlockQuote(out *bytes.Buffer, text []byte) {
+	doubleSpace(out)
+	out.WriteString("<blockquote>\n")
+	out.Write(text)
+	out.WriteString("</blockquote>\n")
+}
+
+func (options *Html) Table(out *bytes.Buffer, header []byte, body []byte, columnData []int) {
+	doubleSpace(out)
+	out.WriteString("<table>\n<thead>\n")
+	out.Write(header)
+	out.WriteString("</thead>\n\n<tbody>\n")
+	out.Write(body)
+	out.WriteString("</tbody>\n</table>\n")
+}
+
+func (options *Html) TableRow(out *bytes.Buffer, text []byte) {
+	doubleSpace(out)
+	out.WriteString("<tr>\n")
+	out.Write(text)
+	out.WriteString("\n</tr>\n")
+}
+
+func (options *Html) TableHeaderCell(out *bytes.Buffer, text []byte, align int) {
+	doubleSpace(out)
+	switch align {
+	case TABLE_ALIGNMENT_LEFT:
+		out.WriteString("<th align=\"left\">")
+	case TABLE_ALIGNMENT_RIGHT:
+		out.WriteString("<th align=\"right\">")
+	case TABLE_ALIGNMENT_CENTER:
+		out.WriteString("<th align=\"center\">")
+	default:
+		out.WriteString("<th>")
+	}
+
+	out.Write(text)
+	out.WriteString("</th>")
+}
+
+func (options *Html) TableCell(out *bytes.Buffer, text []byte, align int) {
+	doubleSpace(out)
+	switch align {
+	case TABLE_ALIGNMENT_LEFT:
+		out.WriteString("<td align=\"left\">")
+	case TABLE_ALIGNMENT_RIGHT:
+		out.WriteString("<td align=\"right\">")
+	case TABLE_ALIGNMENT_CENTER:
+		out.WriteString("<td align=\"center\">")
+	default:
+		out.WriteString("<td>")
+	}
+
+	out.Write(text)
+	out.WriteString("</td>")
+}
+
+func (options *Html) Footnotes(out *bytes.Buffer, text func() bool) {
+	out.WriteString("<div class=\"footnotes\">\n")
+	options.HRule(out)
+	options.List(out, text, LIST_TYPE_ORDERED)
+	out.WriteString("</div>\n")
+}
+
+func (options *Html) FootnoteItem(out *bytes.Buffer, name, text []byte, flags int) {
+	if flags&LIST_ITEM_CONTAINS_BLOCK != 0 || flags&LIST_ITEM_BEGINNING_OF_LIST != 0 {
+		doubleSpace(out)
+	}
+	slug := slugify(name)
+	out.WriteString(`<li id="`)
+	out.WriteString(`fn:`)
+	out.WriteString(options.parameters.FootnoteAnchorPrefix)
+	out.Write(slug)
+	out.WriteString(`">`)
+	out.Write(text)
+	if options.flags&HTML_FOOTNOTE_RETURN_LINKS != 0 {
+		out.WriteString(` <a class="footnote-return" href="#`)
+		out.WriteString(`fnref:`)
+		out.WriteString(options.parameters.FootnoteAnchorPrefix)
+		out.Write(slug)
+		out.WriteString(`">`)
+		out.WriteString(options.parameters.FootnoteReturnLinkContents)
+		out.WriteString(`</a>`)
+	}
+	out.WriteString("</li>\n")
+}
+
+func (options *Html) List(out *bytes.Buffer, text func() bool, flags int) {
+	marker := out.Len()
+	doubleSpace(out)
+
+	if flags&LIST_TYPE_DEFINITION != 0 {
+		out.WriteString("<dl>")
+	} else if flags&LIST_TYPE_ORDERED != 0 {
+		out.WriteString("<ol>")
+	} else {
+		out.WriteString("<ul>")
+	}
+	if !text() {
+		out.Truncate(marker)
+		return
+	}
+	if flags&LIST_TYPE_DEFINITION != 0 {
+		out.WriteString("</dl>\n")
+	} else if flags&LIST_TYPE_ORDERED != 0 {
+		out.WriteString("</ol>\n")
+	} else {
+		out.WriteString("</ul>\n")
+	}
+}
+
+func (options *Html) ListItem(out *bytes.Buffer, text []byte, flags int) {
+	if (flags&LIST_ITEM_CONTAINS_BLOCK != 0 && flags&LIST_TYPE_DEFINITION == 0) ||
+		flags&LIST_ITEM_BEGINNING_OF_LIST != 0 {
+		doubleSpace(out)
+	}
+	if flags&LIST_TYPE_TERM != 0 {
+		out.WriteString("<dt>")
+	} else if flags&LIST_TYPE_DEFINITION != 0 {
+		out.WriteString("<dd>")
+	} else {
+		out.WriteString("<li>")
+	}
+	out.Write(text)
+	if flags&LIST_TYPE_TERM != 0 {
+		out.WriteString("</dt>\n")
+	} else if flags&LIST_TYPE_DEFINITION != 0 {
+		out.WriteString("</dd>\n")
+	} else {
+		out.WriteString("</li>\n")
+	}
+}
+
+func (options *Html) Paragraph(out *bytes.Buffer, text func() bool) {
+	marker := out.Len()
+	doubleSpace(out)
+
+	out.WriteString("<p>")
+	if !text() {
+		out.Truncate(marker)
+		return
+	}
+	out.WriteString("</p>\n")
+}
+
+func (options *Html) AutoLink(out *bytes.Buffer, link []byte, kind int) {
+	skipRanges := htmlEntity.FindAllIndex(link, -1)
+	if options.flags&HTML_SAFELINK != 0 && !isSafeLink(link) && kind != LINK_TYPE_EMAIL {
+		// mark it but don't link it if it is not a safe link: no smartypants
+		out.WriteString("<tt>")
+		entityEscapeWithSkip(out, link, skipRanges)
+		out.WriteString("</tt>")
+		return
+	}
+
+	out.WriteString("<a href=\"")
+	if kind == LINK_TYPE_EMAIL {
+		out.WriteString("mailto:")
+	} else {
+		options.maybeWriteAbsolutePrefix(out, link)
+	}
+
+	entityEscapeWithSkip(out, link, skipRanges)
+
+	var relAttrs []string
+	if options.flags&HTML_NOFOLLOW_LINKS != 0 && !isRelativeLink(link) {
+		relAttrs = append(relAttrs, "nofollow")
+	}
+	if options.flags&HTML_NOREFERRER_LINKS != 0 && !isRelativeLink(link) {
+		relAttrs = append(relAttrs, "noreferrer")
+	}
+	if len(relAttrs) > 0 {
+		out.WriteString(fmt.Sprintf("\" rel=\"%s", strings.Join(relAttrs, " ")))
+	}
+
+	// blank target only add to external link
+	if options.flags&HTML_HREF_TARGET_BLANK != 0 && !isRelativeLink(link) {
+		out.WriteString("\" target=\"_blank")
+	}
+
+	out.WriteString("\">")
+
+	// Pretty print: if we get an email address as
+	// an actual URI, e.g. `mailto:foo@bar.com`, we don't
+	// want to print the `mailto:` prefix
+	switch {
+	case bytes.HasPrefix(link, []byte("mailto://")):
+		attrEscape(out, link[len("mailto://"):])
+	case bytes.HasPrefix(link, []byte("mailto:")):
+		attrEscape(out, link[len("mailto:"):])
+	default:
+		entityEscapeWithSkip(out, link, skipRanges)
+	}
+
+	out.WriteString("</a>")
+}
+
+func (options *Html) CodeSpan(out *bytes.Buffer, text []byte) {
+	out.WriteString("<code>")
+	attrEscape(out, text)
+	out.WriteString("</code>")
+}
+
+func (options *Html) DoubleEmphasis(out *bytes.Buffer, text []byte) {
+	out.WriteString("<strong>")
+	out.Write(text)
+	out.WriteString("</strong>")
+}
+
+func (options *Html) Emphasis(out *bytes.Buffer, text []byte) {
+	if len(text) == 0 {
+		return
+	}
+	out.WriteString("<em>")
+	out.Write(text)
+	out.WriteString("</em>")
+}
+
+func (options *Html) maybeWriteAbsolutePrefix(out *bytes.Buffer, link []byte) {
+	if options.parameters.AbsolutePrefix != "" && isRelativeLink(link) && link[0] != '.' {
+		out.WriteString(options.parameters.AbsolutePrefix)
+		if link[0] != '/' {
+			out.WriteByte('/')
+		}
+	}
+}
+
+func (options *Html) Image(out *bytes.Buffer, link []byte, title []byte, alt []byte) {
+	if options.flags&HTML_SKIP_IMAGES != 0 {
+		return
+	}
+
+	out.WriteString("<img src=\"")
+	options.maybeWriteAbsolutePrefix(out, link)
+	attrEscape(out, link)
+	out.WriteString("\" alt=\"")
+	if len(alt) > 0 {
+		attrEscape(out, alt)
+	}
+	if len(title) > 0 {
+		out.WriteString("\" title=\"")
+		attrEscape(out, title)
+	}
+
+	out.WriteByte('"')
+	out.WriteString(options.closeTag)
+}
+
+func (options *Html) LineBreak(out *bytes.Buffer) {
+	out.WriteString("<br")
+	out.WriteString(options.closeTag)
+	out.WriteByte('\n')
+}
+
+func (options *Html) Link(out *bytes.Buffer, link []byte, title []byte, content []byte) {
+	if options.flags&HTML_SKIP_LINKS != 0 {
+		// write the link text out but don't link it, just mark it with typewriter font
+		out.WriteString("<tt>")
+		attrEscape(out, content)
+		out.WriteString("</tt>")
+		return
+	}
+
+	if options.flags&HTML_SAFELINK != 0 && !isSafeLink(link) {
+		// write the link text out but don't link it, just mark it with typewriter font
+		out.WriteString("<tt>")
+		attrEscape(out, content)
+		out.WriteString("</tt>")
+		return
+	}
+
+	out.WriteString("<a href=\"")
+	options.maybeWriteAbsolutePrefix(out, link)
+	attrEscape(out, link)
+	if len(title) > 0 {
+		out.WriteString("\" title=\"")
+		attrEscape(out, title)
+	}
+	var relAttrs []string
+	if options.flags&HTML_NOFOLLOW_LINKS != 0 && !isRelativeLink(link) {
+		relAttrs = append(relAttrs, "nofollow")
+	}
+	if options.flags&HTML_NOREFERRER_LINKS != 0 && !isRelativeLink(link) {
+		relAttrs = append(relAttrs, "noreferrer")
+	}
+	if len(relAttrs) > 0 {
+		out.WriteString(fmt.Sprintf("\" rel=\"%s", strings.Join(relAttrs, " ")))
+	}
+
+	// blank target only add to external link
+	if options.flags&HTML_HREF_TARGET_BLANK != 0 && !isRelativeLink(link) {
+		out.WriteString("\" target=\"_blank")
+	}
+
+	out.WriteString("\">")
+	out.Write(content)
+	out.WriteString("</a>")
+	return
+}
+
+func (options *Html) RawHtmlTag(out *bytes.Buffer, text []byte) {
+	if options.flags&HTML_SKIP_HTML != 0 {
+		return
+	}
+	if options.flags&HTML_SKIP_STYLE != 0 && isHtmlTag(text, "style") {
+		return
+	}
+	if options.flags&HTML_SKIP_LINKS != 0 && isHtmlTag(text, "a") {
+		return
+	}
+	if options.flags&HTML_SKIP_IMAGES != 0 && isHtmlTag(text, "img") {
+		return
+	}
+	out.Write(text)
+}
+
+func (options *Html) TripleEmphasis(out *bytes.Buffer, text []byte) {
+	out.WriteString("<strong><em>")
+	out.Write(text)
+	out.WriteString("</em></strong>")
+}
+
+func (options *Html) StrikeThrough(out *bytes.Buffer, text []byte) {
+	out.WriteString("<del>")
+	out.Write(text)
+	out.WriteString("</del>")
+}
+
+func (options *Html) FootnoteRef(out *bytes.Buffer, ref []byte, id int) {
+	slug := slugify(ref)
+	out.WriteString(`<sup class="footnote-ref" id="`)
+	out.WriteString(`fnref:`)
+	out.WriteString(options.parameters.FootnoteAnchorPrefix)
+	out.Write(slug)
+	out.WriteString(`"><a href="#`)
+	out.WriteString(`fn:`)
+	out.WriteString(options.parameters.FootnoteAnchorPrefix)
+	out.Write(slug)
+	out.WriteString(`">`)
+	out.WriteString(strconv.Itoa(id))
+	out.WriteString(`</a></sup>`)
+}
+
+func (options *Html) Entity(out *bytes.Buffer, entity []byte) {
+	out.Write(entity)
+}
+
+func (options *Html) NormalText(out *bytes.Buffer, text []byte) {
+	if options.flags&HTML_USE_SMARTYPANTS != 0 {
+		options.Smartypants(out, text)
+	} else {
+		attrEscape(out, text)
+	}
+}
+
+func (options *Html) Smartypants(out *bytes.Buffer, text []byte) {
+	smrt := smartypantsData{false, false}
+
+	// first do normal entity escaping
+	var escaped bytes.Buffer
+	attrEscape(&escaped, text)
+	text = escaped.Bytes()
+
+	mark := 0
+	for i := 0; i < len(text); i++ {
+		if action := options.smartypants[text[i]]; action != nil {
+			if i > mark {
+				out.Write(text[mark:i])
+			}
+
+			previousChar := byte(0)
+			if i > 0 {
+				previousChar = text[i-1]
+			}
+			i += action(out, &smrt, previousChar, text[i:])
+			mark = i + 1
+		}
+	}
+
+	if mark < len(text) {
+		out.Write(text[mark:])
+	}
+}
+
+func (options *Html) DocumentHeader(out *bytes.Buffer) {
+	if options.flags&HTML_COMPLETE_PAGE == 0 {
+		return
+	}
+
+	ending := ""
+	if options.flags&HTML_USE_XHTML != 0 {
+		out.WriteString("<!DOCTYPE html PUBLIC \"-//W3C//DTD XHTML 1.0 Transitional//EN\" ")
+		out.WriteString("\"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\">\n")
+		out.WriteString("<html xmlns=\"http://www.w3.org/1999/xhtml\">\n")
+		ending = " /"
+	} else {
+		out.WriteString("<!DOCTYPE html>\n")
+		out.WriteString("<html>\n")
+	}
+	out.WriteString("<head>\n")
+	out.WriteString("  <title>")
+	options.NormalText(out, []byte(options.title))
+	out.WriteString("</title>\n")
+	out.WriteString("  <meta name=\"GENERATOR\" content=\"Blackfriday Markdown Processor v")
+	out.WriteString(VERSION)
+	out.WriteString("\"")
+	out.WriteString(ending)
+	out.WriteString(">\n")
+	out.WriteString("  <meta charset=\"utf-8\"")
+	out.WriteString(ending)
+	out.WriteString(">\n")
+	if options.css != "" {
+		out.WriteString("  <link rel=\"stylesheet\" type=\"text/css\" href=\"")
+		attrEscape(out, []byte(options.css))
+		out.WriteString("\"")
+		out.WriteString(ending)
+		out.WriteString(">\n")
+	}
+	out.WriteString("</head>\n")
+	out.WriteString("<body>\n")
+
+	options.tocMarker = out.Len()
+}
+
+func (options *Html) DocumentFooter(out *bytes.Buffer) {
+	// finalize and insert the table of contents
+	if options.flags&HTML_TOC != 0 {
+		options.TocFinalize()
+
+		// now we have to insert the table of contents into the document
+		var temp bytes.Buffer
+
+		// start by making a copy of everything after the document header
+		temp.Write(out.Bytes()[options.tocMarker:])
+
+		// now clear the copied material from the main output buffer
+		out.Truncate(options.tocMarker)
+
+		// corner case spacing issue
+		if options.flags&HTML_COMPLETE_PAGE != 0 {
+			out.WriteByte('\n')
+		}
+
+		// insert the table of contents
+		out.WriteString("<nav>\n")
+		out.Write(options.toc.Bytes())
+		out.WriteString("</nav>\n")
+
+		// corner case spacing issue
+		if options.flags&HTML_COMPLETE_PAGE == 0 && options.flags&HTML_OMIT_CONTENTS == 0 {
+			out.WriteByte('\n')
+		}
+
+		// write out everything that came after it
+		if options.flags&HTML_OMIT_CONTENTS == 0 {
+			out.Write(temp.Bytes())
+		}
+	}
+
+	if options.flags&HTML_COMPLETE_PAGE != 0 {
+		out.WriteString("\n</body>\n")
+		out.WriteString("</html>\n")
+	}
+
+}
+
+func (options *Html) TocHeaderWithAnchor(text []byte, level int, anchor string) {
+	for level > options.currentLevel {
+		switch {
+		case bytes.HasSuffix(options.toc.Bytes(), []byte("</li>\n")):
+			// this sublist can nest underneath a header
+			size := options.toc.Len()
+			options.toc.Truncate(size - len("</li>\n"))
+
+		case options.currentLevel > 0:
+			options.toc.WriteString("<li>")
+		}
+		if options.toc.Len() > 0 {
+			options.toc.WriteByte('\n')
+		}
+		options.toc.WriteString("<ul>\n")
+		options.currentLevel++
+	}
+
+	for level < options.currentLevel {
+		options.toc.WriteString("</ul>")
+		if options.currentLevel > 1 {
+			options.toc.WriteString("</li>\n")
+		}
+		options.currentLevel--
+	}
+
+	options.toc.WriteString("<li><a href=\"#")
+	if anchor != "" {
+		options.toc.WriteString(anchor)
+	} else {
+		options.toc.WriteString("toc_")
+		options.toc.WriteString(strconv.Itoa(options.headerCount))
+	}
+	options.toc.WriteString("\">")
+	options.headerCount++
+
+	options.toc.Write(text)
+
+	options.toc.WriteString("</a></li>\n")
+}
+
+func (options *Html) TocHeader(text []byte, level int) {
+	options.TocHeaderWithAnchor(text, level, "")
+}
+
+func (options *Html) TocFinalize() {
+	for options.currentLevel > 1 {
+		options.toc.WriteString("</ul></li>\n")
+		options.currentLevel--
+	}
+
+	if options.currentLevel > 0 {
+		options.toc.WriteString("</ul>\n")
+	}
+}
+
+func isHtmlTag(tag []byte, tagname string) bool {
+	found, _ := findHtmlTagPos(tag, tagname)
+	return found
+}
+
+// Look for a character, but ignore it when it's in any kind of quotes, it
+// might be JavaScript
+func skipUntilCharIgnoreQuotes(html []byte, start int, char byte) int {
+	inSingleQuote := false
+	inDoubleQuote := false
+	inGraveQuote := false
+	i := start
+	for i < len(html) {
+		switch {
+		case html[i] == char && !inSingleQuote && !inDoubleQuote && !inGraveQuote:
+			return i
+		case html[i] == '\'':
+			inSingleQuote = !inSingleQuote
+		case html[i] == '"':
+			inDoubleQuote = !inDoubleQuote
+		case html[i] == '`':
+			inGraveQuote = !inGraveQuote
+		}
+		i++
+	}
+	return start
+}
+
+func findHtmlTagPos(tag []byte, tagname string) (bool, int) {
+	i := 0
+	if i < len(tag) && tag[0] != '<' {
+		return false, -1
+	}
+	i++
+	i = skipSpace(tag, i)
+
+	if i < len(tag) && tag[i] == '/' {
+		i++
+	}
+
+	i = skipSpace(tag, i)
+	j := 0
+	for ; i < len(tag); i, j = i+1, j+1 {
+		if j >= len(tagname) {
+			break
+		}
+
+		if strings.ToLower(string(tag[i]))[0] != tagname[j] {
+			return false, -1
+		}
+	}
+
+	if i == len(tag) {
+		return false, -1
+	}
+
+	rightAngle := skipUntilCharIgnoreQuotes(tag, i, '>')
+	if rightAngle > i {
+		return true, rightAngle
+	}
+
+	return false, -1
+}
+
+func skipUntilChar(text []byte, start int, char byte) int {
+	i := start
+	for i < len(text) && text[i] != char {
+		i++
+	}
+	return i
+}
+
+func skipSpace(tag []byte, i int) int {
+	for i < len(tag) && isspace(tag[i]) {
+		i++
+	}
+	return i
+}
+
+func skipChar(data []byte, start int, char byte) int {
+	i := start
+	for i < len(data) && data[i] == char {
+		i++
+	}
+	return i
+}
+
+func doubleSpace(out *bytes.Buffer) {
+	if out.Len() > 0 {
+		out.WriteByte('\n')
+	}
+}
+
+func isRelativeLink(link []byte) (yes bool) {
+	// a tag begin with '#'
+	if link[0] == '#' {
+		return true
+	}
+
+	// link begin with '/' but not '//', the second maybe a protocol relative link
+	if len(link) >= 2 && link[0] == '/' && link[1] != '/' {
+		return true
+	}
+
+	// only the root '/'
+	if len(link) == 1 && link[0] == '/' {
+		return true
+	}
+
+	// current directory : begin with "./"
+	if bytes.HasPrefix(link, []byte("./")) {
+		return true
+	}
+
+	// parent directory : begin with "../"
+	if bytes.HasPrefix(link, []byte("../")) {
+		return true
+	}
+
+	return false
+}
+
+func (options *Html) ensureUniqueHeaderID(id string) string {
+	for count, found := options.headerIDs[id]; found; count, found = options.headerIDs[id] {
+		tmp := fmt.Sprintf("%s-%d", id, count+1)
+
+		if _, tmpFound := options.headerIDs[tmp]; !tmpFound {
+			options.headerIDs[id] = count + 1
+			id = tmp
+		} else {
+			id = id + "-1"
+		}
+	}
+
+	if _, found := options.headerIDs[id]; !found {
+		options.headerIDs[id] = 0
+	}
+
+	return id
+}
diff --git a/vendor/github.com/russross/blackfriday/inline.go b/vendor/github.com/russross/blackfriday/inline.go
new file mode 100644
index 00000000..4483b8f1
--- /dev/null
+++ b/vendor/github.com/russross/blackfriday/inline.go
@@ -0,0 +1,1154 @@
+//
+// Blackfriday Markdown Processor
+// Available at http://github.com/russross/blackfriday
+//
+// Copyright © 2011 Russ Ross <russ@russross.com>.
+// Distributed under the Simplified BSD License.
+// See README.md for details.
+//
+
+//
+// Functions to parse inline elements.
+//
+
+package blackfriday
+
+import (
+	"bytes"
+	"regexp"
+	"strconv"
+)
+
+var (
+	urlRe    = `((https?|ftp):\/\/|\/)[-A-Za-z0-9+&@#\/%?=~_|!:,.;\(\)]+`
+	anchorRe = regexp.MustCompile(`^(<a\shref="` + urlRe + `"(\stitle="[^"<>]+")?\s?>` + urlRe + `<\/a>)`)
+)
+
+// Functions to parse text within a block
+// Each function returns the number of chars taken care of
+// data is the complete block being rendered
+// offset is the number of valid chars before the current cursor
+
+func (p *parser) inline(out *bytes.Buffer, data []byte) {
+	// this is called recursively: enforce a maximum depth
+	if p.nesting >= p.maxNesting {
+		return
+	}
+	p.nesting++
+
+	i, end := 0, 0
+	for i < len(data) {
+		// copy inactive chars into the output
+		for end < len(data) && p.inlineCallback[data[end]] == nil {
+			end++
+		}
+
+		p.r.NormalText(out, data[i:end])
+
+		if end >= len(data) {
+			break
+		}
+		i = end
+
+		// call the trigger
+		handler := p.inlineCallback[data[end]]
+		if consumed := handler(p, out, data, i); consumed == 0 {
+			// no action from the callback; buffer the byte for later
+			end = i + 1
+		} else {
+			// skip past whatever the callback used
+			i += consumed
+			end = i
+		}
+	}
+
+	p.nesting--
+}
+
+// single and double emphasis parsing
+func emphasis(p *parser, out *bytes.Buffer, data []byte, offset int) int {
+	data = data[offset:]
+	c := data[0]
+	ret := 0
+
+	if len(data) > 2 && data[1] != c {
+		// whitespace cannot follow an opening emphasis;
+		// strikethrough only takes two characters '~~'
+		if c == '~' || isspace(data[1]) {
+			return 0
+		}
+		if ret = helperEmphasis(p, out, data[1:], c); ret == 0 {
+			return 0
+		}
+
+		return ret + 1
+	}
+
+	if len(data) > 3 && data[1] == c && data[2] != c {
+		if isspace(data[2]) {
+			return 0
+		}
+		if ret = helperDoubleEmphasis(p, out, data[2:], c); ret == 0 {
+			return 0
+		}
+
+		return ret + 2
+	}
+
+	if len(data) > 4 && data[1] == c && data[2] == c && data[3] != c {
+		if c == '~' || isspace(data[3]) {
+			return 0
+		}
+		if ret = helperTripleEmphasis(p, out, data, 3, c); ret == 0 {
+			return 0
+		}
+
+		return ret + 3
+	}
+
+	return 0
+}
+
+func codeSpan(p *parser, out *bytes.Buffer, data []byte, offset int) int {
+	data = data[offset:]
+
+	nb := 0
+
+	// count the number of backticks in the delimiter
+	for nb < len(data) && data[nb] == '`' {
+		nb++
+	}
+
+	// find the next delimiter
+	i, end := 0, 0
+	for end = nb; end < len(data) && i < nb; end++ {
+		if data[end] == '`' {
+			i++
+		} else {
+			i = 0
+		}
+	}
+
+	// no matching delimiter?
+	if i < nb && end >= len(data) {
+		return 0
+	}
+
+	// trim outside whitespace
+	fBegin := nb
+	for fBegin < end && data[fBegin] == ' ' {
+		fBegin++
+	}
+
+	fEnd := end - nb
+	for fEnd > fBegin && data[fEnd-1] == ' ' {
+		fEnd--
+	}
+
+	// render the code span
+	if fBegin != fEnd {
+		p.r.CodeSpan(out, data[fBegin:fEnd])
+	}
+
+	return end
+
+}
+
+// newline preceded by two spaces becomes <br>
+// newline without two spaces works when EXTENSION_HARD_LINE_BREAK is enabled
+func lineBreak(p *parser, out *bytes.Buffer, data []byte, offset int) int {
+	// remove trailing spaces from out
+	outBytes := out.Bytes()
+	end := len(outBytes)
+	eol := end
+	for eol > 0 && outBytes[eol-1] == ' ' {
+		eol--
+	}
+	out.Truncate(eol)
+
+	precededByTwoSpaces := offset >= 2 && data[offset-2] == ' ' && data[offset-1] == ' '
+	precededByBackslash := offset >= 1 && data[offset-1] == '\\' // see http://spec.commonmark.org/0.18/#example-527
+	precededByBackslash = precededByBackslash && p.flags&EXTENSION_BACKSLASH_LINE_BREAK != 0
+
+	if p.flags&EXTENSION_JOIN_LINES != 0 {
+		return 1
+	}
+
+	// should there be a hard line break here?
+	if p.flags&EXTENSION_HARD_LINE_BREAK == 0 && !precededByTwoSpaces && !precededByBackslash {
+		return 0
+	}
+
+	if precededByBackslash && eol > 0 {
+		out.Truncate(eol - 1)
+	}
+	p.r.LineBreak(out)
+	return 1
+}
+
+type linkType int
+
+const (
+	linkNormal linkType = iota
+	linkImg
+	linkDeferredFootnote
+	linkInlineFootnote
+)
+
+func isReferenceStyleLink(data []byte, pos int, t linkType) bool {
+	if t == linkDeferredFootnote {
+		return false
+	}
+	return pos < len(data)-1 && data[pos] == '[' && data[pos+1] != '^'
+}
+
+// '[': parse a link or an image or a footnote
+func link(p *parser, out *bytes.Buffer, data []byte, offset int) int {
+	// no links allowed inside regular links, footnote, and deferred footnotes
+	if p.insideLink && (offset > 0 && data[offset-1] == '[' || len(data)-1 > offset && data[offset+1] == '^') {
+		return 0
+	}
+
+	var t linkType
+	switch {
+	// special case: ![^text] == deferred footnote (that follows something with
+	// an exclamation point)
+	case p.flags&EXTENSION_FOOTNOTES != 0 && len(data)-1 > offset && data[offset+1] == '^':
+		t = linkDeferredFootnote
+	// ![alt] == image
+	case offset > 0 && data[offset-1] == '!':
+		t = linkImg
+	// ^[text] == inline footnote
+	// [^refId] == deferred footnote
+	case p.flags&EXTENSION_FOOTNOTES != 0:
+		if offset > 0 && data[offset-1] == '^' {
+			t = linkInlineFootnote
+		} else if len(data)-1 > offset && data[offset+1] == '^' {
+			t = linkDeferredFootnote
+		}
+	// [text] == regular link
+	default:
+		t = linkNormal
+	}
+
+	data = data[offset:]
+
+	var (
+		i                       = 1
+		noteId                  int
+		title, link, altContent []byte
+		textHasNl               = false
+	)
+
+	if t == linkDeferredFootnote {
+		i++
+	}
+
+	brace := 0
+
+	// look for the matching closing bracket
+	for level := 1; level > 0 && i < len(data); i++ {
+		switch {
+		case data[i] == '\n':
+			textHasNl = true
+
+		case data[i-1] == '\\':
+			continue
+
+		case data[i] == '[':
+			level++
+
+		case data[i] == ']':
+			level--
+			if level <= 0 {
+				i-- // compensate for extra i++ in for loop
+			}
+		}
+	}
+
+	if i >= len(data) {
+		return 0
+	}
+
+	txtE := i
+	i++
+
+	// skip any amount of whitespace or newline
+	// (this is much more lax than original markdown syntax)
+	for i < len(data) && isspace(data[i]) {
+		i++
+	}
+
+	switch {
+	// inline style link
+	case i < len(data) && data[i] == '(':
+		// skip initial whitespace
+		i++
+
+		for i < len(data) && isspace(data[i]) {
+			i++
+		}
+
+		linkB := i
+
+		// look for link end: ' " ), check for new opening braces and take this
+		// into account, this may lead for overshooting and probably will require
+		// some fine-tuning.
+	findlinkend:
+		for i < len(data) {
+			switch {
+			case data[i] == '\\':
+				i += 2
+
+			case data[i] == '(':
+				brace++
+				i++
+
+			case data[i] == ')':
+				if brace <= 0 {
+					break findlinkend
+				}
+				brace--
+				i++
+
+			case data[i] == '\'' || data[i] == '"':
+				break findlinkend
+
+			default:
+				i++
+			}
+		}
+
+		if i >= len(data) {
+			return 0
+		}
+		linkE := i
+
+		// look for title end if present
+		titleB, titleE := 0, 0
+		if data[i] == '\'' || data[i] == '"' {
+			i++
+			titleB = i
+
+		findtitleend:
+			for i < len(data) {
+				switch {
+				case data[i] == '\\':
+					i += 2
+
+				case data[i] == ')':
+					break findtitleend
+
+				default:
+					i++
+				}
+			}
+
+			if i >= len(data) {
+				return 0
+			}
+
+			// skip whitespace after title
+			titleE = i - 1
+			for titleE > titleB && isspace(data[titleE]) {
+				titleE--
+			}
+
+			// check for closing quote presence
+			if data[titleE] != '\'' && data[titleE] != '"' {
+				titleB, titleE = 0, 0
+				linkE = i
+			}
+		}
+
+		// remove whitespace at the end of the link
+		for linkE > linkB && isspace(data[linkE-1]) {
+			linkE--
+		}
+
+		// remove optional angle brackets around the link
+		if data[linkB] == '<' {
+			linkB++
+		}
+		if data[linkE-1] == '>' {
+			linkE--
+		}
+
+		// build escaped link and title
+		if linkE > linkB {
+			link = data[linkB:linkE]
+		}
+
+		if titleE > titleB {
+			title = data[titleB:titleE]
+		}
+
+		i++
+
+	// reference style link
+	case isReferenceStyleLink(data, i, t):
+		var id []byte
+		altContentConsidered := false
+
+		// look for the id
+		i++
+		linkB := i
+		for i < len(data) && data[i] != ']' {
+			i++
+		}
+		if i >= len(data) {
+			return 0
+		}
+		linkE := i
+
+		// find the reference
+		if linkB == linkE {
+			if textHasNl {
+				var b bytes.Buffer
+
+				for j := 1; j < txtE; j++ {
+					switch {
+					case data[j] != '\n':
+						b.WriteByte(data[j])
+					case data[j-1] != ' ':
+						b.WriteByte(' ')
+					}
+				}
+
+				id = b.Bytes()
+			} else {
+				id = data[1:txtE]
+				altContentConsidered = true
+			}
+		} else {
+			id = data[linkB:linkE]
+		}
+
+		// find the reference with matching id
+		lr, ok := p.getRef(string(id))
+		if !ok {
+			return 0
+		}
+
+		// keep link and title from reference
+		link = lr.link
+		title = lr.title
+		if altContentConsidered {
+			altContent = lr.text
+		}
+		i++
+
+	// shortcut reference style link or reference or inline footnote
+	default:
+		var id []byte
+
+		// craft the id
+		if textHasNl {
+			var b bytes.Buffer
+
+			for j := 1; j < txtE; j++ {
+				switch {
+				case data[j] != '\n':
+					b.WriteByte(data[j])
+				case data[j-1] != ' ':
+					b.WriteByte(' ')
+				}
+			}
+
+			id = b.Bytes()
+		} else {
+			if t == linkDeferredFootnote {
+				id = data[2:txtE] // get rid of the ^
+			} else {
+				id = data[1:txtE]
+			}
+		}
+
+		if t == linkInlineFootnote {
+			// create a new reference
+			noteId = len(p.notes) + 1
+
+			var fragment []byte
+			if len(id) > 0 {
+				if len(id) < 16 {
+					fragment = make([]byte, len(id))
+				} else {
+					fragment = make([]byte, 16)
+				}
+				copy(fragment, slugify(id))
+			} else {
+				fragment = append([]byte("footnote-"), []byte(strconv.Itoa(noteId))...)
+			}
+
+			ref := &reference{
+				noteId:   noteId,
+				hasBlock: false,
+				link:     fragment,
+				title:    id,
+			}
+
+			p.notes = append(p.notes, ref)
+			p.notesRecord[string(ref.link)] = struct{}{}
+
+			link = ref.link
+			title = ref.title
+		} else {
+			// find the reference with matching id
+			lr, ok := p.getRef(string(id))
+			if !ok {
+				return 0
+			}
+
+			if t == linkDeferredFootnote && !p.isFootnote(lr) {
+				lr.noteId = len(p.notes) + 1
+				p.notes = append(p.notes, lr)
+				p.notesRecord[string(lr.link)] = struct{}{}
+			}
+
+			// keep link and title from reference
+			link = lr.link
+			// if inline footnote, title == footnote contents
+			title = lr.title
+			noteId = lr.noteId
+		}
+
+		// rewind the whitespace
+		i = txtE + 1
+	}
+
+	// build content: img alt is escaped, link content is parsed
+	var content bytes.Buffer
+	if txtE > 1 {
+		if t == linkImg {
+			content.Write(data[1:txtE])
+		} else {
+			// links cannot contain other links, so turn off link parsing temporarily
+			insideLink := p.insideLink
+			p.insideLink = true
+			p.inline(&content, data[1:txtE])
+			p.insideLink = insideLink
+		}
+	}
+
+	var uLink []byte
+	if t == linkNormal || t == linkImg {
+		if len(link) > 0 {
+			var uLinkBuf bytes.Buffer
+			unescapeText(&uLinkBuf, link)
+			uLink = uLinkBuf.Bytes()
+		}
+
+		// links need something to click on and somewhere to go
+		if len(uLink) == 0 || (t == linkNormal && content.Len() == 0) {
+			return 0
+		}
+	}
+
+	// call the relevant rendering function
+	switch t {
+	case linkNormal:
+		if len(altContent) > 0 {
+			p.r.Link(out, uLink, title, altContent)
+		} else {
+			p.r.Link(out, uLink, title, content.Bytes())
+		}
+
+	case linkImg:
+		outSize := out.Len()
+		outBytes := out.Bytes()
+		if outSize > 0 && outBytes[outSize-1] == '!' {
+			out.Truncate(outSize - 1)
+		}
+
+		p.r.Image(out, uLink, title, content.Bytes())
+
+	case linkInlineFootnote:
+		outSize := out.Len()
+		outBytes := out.Bytes()
+		if outSize > 0 && outBytes[outSize-1] == '^' {
+			out.Truncate(outSize - 1)
+		}
+
+		p.r.FootnoteRef(out, link, noteId)
+
+	case linkDeferredFootnote:
+		p.r.FootnoteRef(out, link, noteId)
+
+	default:
+		return 0
+	}
+
+	return i
+}
+
+func (p *parser) inlineHTMLComment(out *bytes.Buffer, data []byte) int {
+	if len(data) < 5 {
+		return 0
+	}
+	if data[0] != '<' || data[1] != '!' || data[2] != '-' || data[3] != '-' {
+		return 0
+	}
+	i := 5
+	// scan for an end-of-comment marker, across lines if necessary
+	for i < len(data) && !(data[i-2] == '-' && data[i-1] == '-' && data[i] == '>') {
+		i++
+	}
+	// no end-of-comment marker
+	if i >= len(data) {
+		return 0
+	}
+	return i + 1
+}
+
+// '<' when tags or autolinks are allowed
+func leftAngle(p *parser, out *bytes.Buffer, data []byte, offset int) int {
+	data = data[offset:]
+	altype := LINK_TYPE_NOT_AUTOLINK
+	end := tagLength(data, &altype)
+	if size := p.inlineHTMLComment(out, data); size > 0 {
+		end = size
+	}
+	if end > 2 {
+		if altype != LINK_TYPE_NOT_AUTOLINK {
+			var uLink bytes.Buffer
+			unescapeText(&uLink, data[1:end+1-2])
+			if uLink.Len() > 0 {
+				p.r.AutoLink(out, uLink.Bytes(), altype)
+			}
+		} else {
+			p.r.RawHtmlTag(out, data[:end])
+		}
+	}
+
+	return end
+}
+
+// '\\' backslash escape
+var escapeChars = []byte("\\`*_{}[]()#+-.!:|&<>~")
+
+func escape(p *parser, out *bytes.Buffer, data []byte, offset int) int {
+	data = data[offset:]
+
+	if len(data) > 1 {
+		if bytes.IndexByte(escapeChars, data[1]) < 0 {
+			return 0
+		}
+
+		p.r.NormalText(out, data[1:2])
+	}
+
+	return 2
+}
+
+func unescapeText(ob *bytes.Buffer, src []byte) {
+	i := 0
+	for i < len(src) {
+		org := i
+		for i < len(src) && src[i] != '\\' {
+			i++
+		}
+
+		if i > org {
+			ob.Write(src[org:i])
+		}
+
+		if i+1 >= len(src) {
+			break
+		}
+
+		ob.WriteByte(src[i+1])
+		i += 2
+	}
+}
+
+// '&' escaped when it doesn't belong to an entity
+// valid entities are assumed to be anything matching &#?[A-Za-z0-9]+;
+func entity(p *parser, out *bytes.Buffer, data []byte, offset int) int {
+	data = data[offset:]
+
+	end := 1
+
+	if end < len(data) && data[end] == '#' {
+		end++
+	}
+
+	for end < len(data) && isalnum(data[end]) {
+		end++
+	}
+
+	if end < len(data) && data[end] == ';' {
+		end++ // real entity
+	} else {
+		return 0 // lone '&'
+	}
+
+	p.r.Entity(out, data[:end])
+
+	return end
+}
+
+func linkEndsWithEntity(data []byte, linkEnd int) bool {
+	entityRanges := htmlEntity.FindAllIndex(data[:linkEnd], -1)
+	return entityRanges != nil && entityRanges[len(entityRanges)-1][1] == linkEnd
+}
+
+func autoLink(p *parser, out *bytes.Buffer, data []byte, offset int) int {
+	// quick check to rule out most false hits on ':'
+	if p.insideLink || len(data) < offset+3 || data[offset+1] != '/' || data[offset+2] != '/' {
+		return 0
+	}
+
+	// Now a more expensive check to see if we're not inside an anchor element
+	anchorStart := offset
+	offsetFromAnchor := 0
+	for anchorStart > 0 && data[anchorStart] != '<' {
+		anchorStart--
+		offsetFromAnchor++
+	}
+
+	anchorStr := anchorRe.Find(data[anchorStart:])
+	if anchorStr != nil {
+		out.Write(anchorStr[offsetFromAnchor:])
+		return len(anchorStr) - offsetFromAnchor
+	}
+
+	// scan backward for a word boundary
+	rewind := 0
+	for offset-rewind > 0 && rewind <= 7 && isletter(data[offset-rewind-1]) {
+		rewind++
+	}
+	if rewind > 6 { // longest supported protocol is "mailto" which has 6 letters
+		return 0
+	}
+
+	origData := data
+	data = data[offset-rewind:]
+
+	if !isSafeLink(data) {
+		return 0
+	}
+
+	linkEnd := 0
+	for linkEnd < len(data) && !isEndOfLink(data[linkEnd]) {
+		linkEnd++
+	}
+
+	// Skip punctuation at the end of the link
+	if (data[linkEnd-1] == '.' || data[linkEnd-1] == ',') && data[linkEnd-2] != '\\' {
+		linkEnd--
+	}
+
+	// But don't skip semicolon if it's a part of escaped entity:
+	if data[linkEnd-1] == ';' && data[linkEnd-2] != '\\' && !linkEndsWithEntity(data, linkEnd) {
+		linkEnd--
+	}
+
+	// See if the link finishes with a punctuation sign that can be closed.
+	var copen byte
+	switch data[linkEnd-1] {
+	case '"':
+		copen = '"'
+	case '\'':
+		copen = '\''
+	case ')':
+		copen = '('
+	case ']':
+		copen = '['
+	case '}':
+		copen = '{'
+	default:
+		copen = 0
+	}
+
+	if copen != 0 {
+		bufEnd := offset - rewind + linkEnd - 2
+
+		openDelim := 1
+
+		/* Try to close the final punctuation sign in this same line;
+		 * if we managed to close it outside of the URL, that means that it's
+		 * not part of the URL. If it closes inside the URL, that means it
+		 * is part of the URL.
+		 *
+		 * Examples:
+		 *
+		 *      foo http://www.pokemon.com/Pikachu_(Electric) bar
+		 *              => http://www.pokemon.com/Pikachu_(Electric)
+		 *
+		 *      foo (http://www.pokemon.com/Pikachu_(Electric)) bar
+		 *              => http://www.pokemon.com/Pikachu_(Electric)
+		 *
+		 *      foo http://www.pokemon.com/Pikachu_(Electric)) bar
+		 *              => http://www.pokemon.com/Pikachu_(Electric))
+		 *
+		 *      (foo http://www.pokemon.com/Pikachu_(Electric)) bar
+		 *              => foo http://www.pokemon.com/Pikachu_(Electric)
+		 */
+
+		for bufEnd >= 0 && origData[bufEnd] != '\n' && openDelim != 0 {
+			if origData[bufEnd] == data[linkEnd-1] {
+				openDelim++
+			}
+
+			if origData[bufEnd] == copen {
+				openDelim--
+			}
+
+			bufEnd--
+		}
+
+		if openDelim == 0 {
+			linkEnd--
+		}
+	}
+
+	// we were triggered on the ':', so we need to rewind the output a bit
+	if out.Len() >= rewind {
+		out.Truncate(len(out.Bytes()) - rewind)
+	}
+
+	var uLink bytes.Buffer
+	unescapeText(&uLink, data[:linkEnd])
+
+	if uLink.Len() > 0 {
+		p.r.AutoLink(out, uLink.Bytes(), LINK_TYPE_NORMAL)
+	}
+
+	return linkEnd - rewind
+}
+
+func isEndOfLink(char byte) bool {
+	return isspace(char) || char == '<'
+}
+
+var validUris = [][]byte{[]byte("http://"), []byte("https://"), []byte("ftp://"), []byte("mailto://")}
+var validPaths = [][]byte{[]byte("/"), []byte("./"), []byte("../")}
+
+func isSafeLink(link []byte) bool {
+	for _, path := range validPaths {
+		if len(link) >= len(path) && bytes.Equal(link[:len(path)], path) {
+			if len(link) == len(path) {
+				return true
+			} else if isalnum(link[len(path)]) {
+				return true
+			}
+		}
+	}
+
+	for _, prefix := range validUris {
+		// TODO: handle unicode here
+		// case-insensitive prefix test
+		if len(link) > len(prefix) && bytes.Equal(bytes.ToLower(link[:len(prefix)]), prefix) && isalnum(link[len(prefix)]) {
+			return true
+		}
+	}
+
+	return false
+}
+
+// return the length of the given tag, or 0 is it's not valid
+func tagLength(data []byte, autolink *int) int {
+	var i, j int
+
+	// a valid tag can't be shorter than 3 chars
+	if len(data) < 3 {
+		return 0
+	}
+
+	// begins with a '<' optionally followed by '/', followed by letter or number
+	if data[0] != '<' {
+		return 0
+	}
+	if data[1] == '/' {
+		i = 2
+	} else {
+		i = 1
+	}
+
+	if !isalnum(data[i]) {
+		return 0
+	}
+
+	// scheme test
+	*autolink = LINK_TYPE_NOT_AUTOLINK
+
+	// try to find the beginning of an URI
+	for i < len(data) && (isalnum(data[i]) || data[i] == '.' || data[i] == '+' || data[i] == '-') {
+		i++
+	}
+
+	if i > 1 && i < len(data) && data[i] == '@' {
+		if j = isMailtoAutoLink(data[i:]); j != 0 {
+			*autolink = LINK_TYPE_EMAIL
+			return i + j
+		}
+	}
+
+	if i > 2 && i < len(data) && data[i] == ':' {
+		*autolink = LINK_TYPE_NORMAL
+		i++
+	}
+
+	// complete autolink test: no whitespace or ' or "
+	switch {
+	case i >= len(data):
+		*autolink = LINK_TYPE_NOT_AUTOLINK
+	case *autolink != 0:
+		j = i
+
+		for i < len(data) {
+			if data[i] == '\\' {
+				i += 2
+			} else if data[i] == '>' || data[i] == '\'' || data[i] == '"' || isspace(data[i]) {
+				break
+			} else {
+				i++
+			}
+
+		}
+
+		if i >= len(data) {
+			return 0
+		}
+		if i > j && data[i] == '>' {
+			return i + 1
+		}
+
+		// one of the forbidden chars has been found
+		*autolink = LINK_TYPE_NOT_AUTOLINK
+	}
+
+	// look for something looking like a tag end
+	for i < len(data) && data[i] != '>' {
+		i++
+	}
+	if i >= len(data) {
+		return 0
+	}
+	return i + 1
+}
+
+// look for the address part of a mail autolink and '>'
+// this is less strict than the original markdown e-mail address matching
+func isMailtoAutoLink(data []byte) int {
+	nb := 0
+
+	// address is assumed to be: [-@._a-zA-Z0-9]+ with exactly one '@'
+	for i := 0; i < len(data); i++ {
+		if isalnum(data[i]) {
+			continue
+		}
+
+		switch data[i] {
+		case '@':
+			nb++
+
+		case '-', '.', '_':
+			// Do nothing.
+
+		case '>':
+			if nb == 1 {
+				return i + 1
+			} else {
+				return 0
+			}
+		default:
+			return 0
+		}
+	}
+
+	return 0
+}
+
+// look for the next emph char, skipping other constructs
+func helperFindEmphChar(data []byte, c byte) int {
+	i := 0
+
+	for i < len(data) {
+		for i < len(data) && data[i] != c && data[i] != '`' && data[i] != '[' {
+			i++
+		}
+		if i >= len(data) {
+			return 0
+		}
+		// do not count escaped chars
+		if i != 0 && data[i-1] == '\\' {
+			i++
+			continue
+		}
+		if data[i] == c {
+			return i
+		}
+
+		if data[i] == '`' {
+			// skip a code span
+			tmpI := 0
+			i++
+			for i < len(data) && data[i] != '`' {
+				if tmpI == 0 && data[i] == c {
+					tmpI = i
+				}
+				i++
+			}
+			if i >= len(data) {
+				return tmpI
+			}
+			i++
+		} else if data[i] == '[' {
+			// skip a link
+			tmpI := 0
+			i++
+			for i < len(data) && data[i] != ']' {
+				if tmpI == 0 && data[i] == c {
+					tmpI = i
+				}
+				i++
+			}
+			i++
+			for i < len(data) && (data[i] == ' ' || data[i] == '\n') {
+				i++
+			}
+			if i >= len(data) {
+				return tmpI
+			}
+			if data[i] != '[' && data[i] != '(' { // not a link
+				if tmpI > 0 {
+					return tmpI
+				} else {
+					continue
+				}
+			}
+			cc := data[i]
+			i++
+			for i < len(data) && data[i] != cc {
+				if tmpI == 0 && data[i] == c {
+					return i
+				}
+				i++
+			}
+			if i >= len(data) {
+				return tmpI
+			}
+			i++
+		}
+	}
+	return 0
+}
+
+func helperEmphasis(p *parser, out *bytes.Buffer, data []byte, c byte) int {
+	i := 0
+
+	// skip one symbol if coming from emph3
+	if len(data) > 1 && data[0] == c && data[1] == c {
+		i = 1
+	}
+
+	for i < len(data) {
+		length := helperFindEmphChar(data[i:], c)
+		if length == 0 {
+			return 0
+		}
+		i += length
+		if i >= len(data) {
+			return 0
+		}
+
+		if i+1 < len(data) && data[i+1] == c {
+			i++
+			continue
+		}
+
+		if data[i] == c && !isspace(data[i-1]) {
+
+			if p.flags&EXTENSION_NO_INTRA_EMPHASIS != 0 {
+				if !(i+1 == len(data) || isspace(data[i+1]) || ispunct(data[i+1])) {
+					continue
+				}
+			}
+
+			var work bytes.Buffer
+			p.inline(&work, data[:i])
+			p.r.Emphasis(out, work.Bytes())
+			return i + 1
+		}
+	}
+
+	return 0
+}
+
+func helperDoubleEmphasis(p *parser, out *bytes.Buffer, data []byte, c byte) int {
+	i := 0
+
+	for i < len(data) {
+		length := helperFindEmphChar(data[i:], c)
+		if length == 0 {
+			return 0
+		}
+		i += length
+
+		if i+1 < len(data) && data[i] == c && data[i+1] == c && i > 0 && !isspace(data[i-1]) {
+			var work bytes.Buffer
+			p.inline(&work, data[:i])
+
+			if work.Len() > 0 {
+				// pick the right renderer
+				if c == '~' {
+					p.r.StrikeThrough(out, work.Bytes())
+				} else {
+					p.r.DoubleEmphasis(out, work.Bytes())
+				}
+			}
+			return i + 2
+		}
+		i++
+	}
+	return 0
+}
+
+func helperTripleEmphasis(p *parser, out *bytes.Buffer, data []byte, offset int, c byte) int {
+	i := 0
+	origData := data
+	data = data[offset:]
+
+	for i < len(data) {
+		length := helperFindEmphChar(data[i:], c)
+		if length == 0 {
+			return 0
+		}
+		i += length
+
+		// skip whitespace preceded symbols
+		if data[i] != c || isspace(data[i-1]) {
+			continue
+		}
+
+		switch {
+		case i+2 < len(data) && data[i+1] == c && data[i+2] == c:
+			// triple symbol found
+			var work bytes.Buffer
+
+			p.inline(&work, data[:i])
+			if work.Len() > 0 {
+				p.r.TripleEmphasis(out, work.Bytes())
+			}
+			return i + 3
+		case (i+1 < len(data) && data[i+1] == c):
+			// double symbol found, hand over to emph1
+			length = helperEmphasis(p, out, origData[offset-2:], c)
+			if length == 0 {
+				return 0
+			} else {
+				return length - 2
+			}
+		default:
+			// single symbol found, hand over to emph2
+			length = helperDoubleEmphasis(p, out, origData[offset-1:], c)
+			if length == 0 {
+				return 0
+			} else {
+				return length - 1
+			}
+		}
+	}
+	return 0
+}
diff --git a/vendor/github.com/russross/blackfriday/latex.go b/vendor/github.com/russross/blackfriday/latex.go
new file mode 100644
index 00000000..70705aa9
--- /dev/null
+++ b/vendor/github.com/russross/blackfriday/latex.go
@@ -0,0 +1,332 @@
+//
+// Blackfriday Markdown Processor
+// Available at http://github.com/russross/blackfriday
+//
+// Copyright © 2011 Russ Ross <russ@russross.com>.
+// Distributed under the Simplified BSD License.
+// See README.md for details.
+//
+
+//
+//
+// LaTeX rendering backend
+//
+//
+
+package blackfriday
+
+import (
+	"bytes"
+)
+
+// Latex is a type that implements the Renderer interface for LaTeX output.
+//
+// Do not create this directly, instead use the LatexRenderer function.
+type Latex struct {
+}
+
+// LatexRenderer creates and configures a Latex object, which
+// satisfies the Renderer interface.
+//
+// flags is a set of LATEX_* options ORed together (currently no such options
+// are defined).
+func LatexRenderer(flags int) Renderer {
+	return &Latex{}
+}
+
+func (options *Latex) GetFlags() int {
+	return 0
+}
+
+// render code chunks using verbatim, or listings if we have a language
+func (options *Latex) BlockCode(out *bytes.Buffer, text []byte, lang string) {
+	if lang == "" {
+		out.WriteString("\n\\begin{verbatim}\n")
+	} else {
+		out.WriteString("\n\\begin{lstlisting}[language=")
+		out.WriteString(lang)
+		out.WriteString("]\n")
+	}
+	out.Write(text)
+	if lang == "" {
+		out.WriteString("\n\\end{verbatim}\n")
+	} else {
+		out.WriteString("\n\\end{lstlisting}\n")
+	}
+}
+
+func (options *Latex) TitleBlock(out *bytes.Buffer, text []byte) {
+
+}
+
+func (options *Latex) BlockQuote(out *bytes.Buffer, text []byte) {
+	out.WriteString("\n\\begin{quotation}\n")
+	out.Write(text)
+	out.WriteString("\n\\end{quotation}\n")
+}
+
+func (options *Latex) BlockHtml(out *bytes.Buffer, text []byte) {
+	// a pretty lame thing to do...
+	out.WriteString("\n\\begin{verbatim}\n")
+	out.Write(text)
+	out.WriteString("\n\\end{verbatim}\n")
+}
+
+func (options *Latex) Header(out *bytes.Buffer, text func() bool, level int, id string) {
+	marker := out.Len()
+
+	switch level {
+	case 1:
+		out.WriteString("\n\\section{")
+	case 2:
+		out.WriteString("\n\\subsection{")
+	case 3:
+		out.WriteString("\n\\subsubsection{")
+	case 4:
+		out.WriteString("\n\\paragraph{")
+	case 5:
+		out.WriteString("\n\\subparagraph{")
+	case 6:
+		out.WriteString("\n\\textbf{")
+	}
+	if !text() {
+		out.Truncate(marker)
+		return
+	}
+	out.WriteString("}\n")
+}
+
+func (options *Latex) HRule(out *bytes.Buffer) {
+	out.WriteString("\n\\HRule\n")
+}
+
+func (options *Latex) List(out *bytes.Buffer, text func() bool, flags int) {
+	marker := out.Len()
+	if flags&LIST_TYPE_ORDERED != 0 {
+		out.WriteString("\n\\begin{enumerate}\n")
+	} else {
+		out.WriteString("\n\\begin{itemize}\n")
+	}
+	if !text() {
+		out.Truncate(marker)
+		return
+	}
+	if flags&LIST_TYPE_ORDERED != 0 {
+		out.WriteString("\n\\end{enumerate}\n")
+	} else {
+		out.WriteString("\n\\end{itemize}\n")
+	}
+}
+
+func (options *Latex) ListItem(out *bytes.Buffer, text []byte, flags int) {
+	out.WriteString("\n\\item ")
+	out.Write(text)
+}
+
+func (options *Latex) Paragraph(out *bytes.Buffer, text func() bool) {
+	marker := out.Len()
+	out.WriteString("\n")
+	if !text() {
+		out.Truncate(marker)
+		return
+	}
+	out.WriteString("\n")
+}
+
+func (options *Latex) Table(out *bytes.Buffer, header []byte, body []byte, columnData []int) {
+	out.WriteString("\n\\begin{tabular}{")
+	for _, elt := range columnData {
+		switch elt {
+		case TABLE_ALIGNMENT_LEFT:
+			out.WriteByte('l')
+		case TABLE_ALIGNMENT_RIGHT:
+			out.WriteByte('r')
+		default:
+			out.WriteByte('c')
+		}
+	}
+	out.WriteString("}\n")
+	out.Write(header)
+	out.WriteString(" \\\\\n\\hline\n")
+	out.Write(body)
+	out.WriteString("\n\\end{tabular}\n")
+}
+
+func (options *Latex) TableRow(out *bytes.Buffer, text []byte) {
+	if out.Len() > 0 {
+		out.WriteString(" \\\\\n")
+	}
+	out.Write(text)
+}
+
+func (options *Latex) TableHeaderCell(out *bytes.Buffer, text []byte, align int) {
+	if out.Len() > 0 {
+		out.WriteString(" & ")
+	}
+	out.Write(text)
+}
+
+func (options *Latex) TableCell(out *bytes.Buffer, text []byte, align int) {
+	if out.Len() > 0 {
+		out.WriteString(" & ")
+	}
+	out.Write(text)
+}
+
+// TODO: this
+func (options *Latex) Footnotes(out *bytes.Buffer, text func() bool) {
+
+}
+
+func (options *Latex) FootnoteItem(out *bytes.Buffer, name, text []byte, flags int) {
+
+}
+
+func (options *Latex) AutoLink(out *bytes.Buffer, link []byte, kind int) {
+	out.WriteString("\\href{")
+	if kind == LINK_TYPE_EMAIL {
+		out.WriteString("mailto:")
+	}
+	out.Write(link)
+	out.WriteString("}{")
+	out.Write(link)
+	out.WriteString("}")
+}
+
+func (options *Latex) CodeSpan(out *bytes.Buffer, text []byte) {
+	out.WriteString("\\texttt{")
+	escapeSpecialChars(out, text)
+	out.WriteString("}")
+}
+
+func (options *Latex) DoubleEmphasis(out *bytes.Buffer, text []byte) {
+	out.WriteString("\\textbf{")
+	out.Write(text)
+	out.WriteString("}")
+}
+
+func (options *Latex) Emphasis(out *bytes.Buffer, text []byte) {
+	out.WriteString("\\textit{")
+	out.Write(text)
+	out.WriteString("}")
+}
+
+func (options *Latex) Image(out *bytes.Buffer, link []byte, title []byte, alt []byte) {
+	if bytes.HasPrefix(link, []byte("http://")) || bytes.HasPrefix(link, []byte("https://")) {
+		// treat it like a link
+		out.WriteString("\\href{")
+		out.Write(link)
+		out.WriteString("}{")
+		out.Write(alt)
+		out.WriteString("}")
+	} else {
+		out.WriteString("\\includegraphics{")
+		out.Write(link)
+		out.WriteString("}")
+	}
+}
+
+func (options *Latex) LineBreak(out *bytes.Buffer) {
+	out.WriteString(" \\\\\n")
+}
+
+func (options *Latex) Link(out *bytes.Buffer, link []byte, title []byte, content []byte) {
+	out.WriteString("\\href{")
+	out.Write(link)
+	out.WriteString("}{")
+	out.Write(content)
+	out.WriteString("}")
+}
+
+func (options *Latex) RawHtmlTag(out *bytes.Buffer, tag []byte) {
+}
+
+func (options *Latex) TripleEmphasis(out *bytes.Buffer, text []byte) {
+	out.WriteString("\\textbf{\\textit{")
+	out.Write(text)
+	out.WriteString("}}")
+}
+
+func (options *Latex) StrikeThrough(out *bytes.Buffer, text []byte) {
+	out.WriteString("\\sout{")
+	out.Write(text)
+	out.WriteString("}")
+}
+
+// TODO: this
+func (options *Latex) FootnoteRef(out *bytes.Buffer, ref []byte, id int) {
+
+}
+
+func needsBackslash(c byte) bool {
+	for _, r := range []byte("_{}%$&\\~#") {
+		if c == r {
+			return true
+		}
+	}
+	return false
+}
+
+func escapeSpecialChars(out *bytes.Buffer, text []byte) {
+	for i := 0; i < len(text); i++ {
+		// directly copy normal characters
+		org := i
+
+		for i < len(text) && !needsBackslash(text[i]) {
+			i++
+		}
+		if i > org {
+			out.Write(text[org:i])
+		}
+
+		// escape a character
+		if i >= len(text) {
+			break
+		}
+		out.WriteByte('\\')
+		out.WriteByte(text[i])
+	}
+}
+
+func (options *Latex) Entity(out *bytes.Buffer, entity []byte) {
+	// TODO: convert this into a unicode character or something
+	out.Write(entity)
+}
+
+func (options *Latex) NormalText(out *bytes.Buffer, text []byte) {
+	escapeSpecialChars(out, text)
+}
+
+// header and footer
+func (options *Latex) DocumentHeader(out *bytes.Buffer) {
+	out.WriteString("\\documentclass{article}\n")
+	out.WriteString("\n")
+	out.WriteString("\\usepackage{graphicx}\n")
+	out.WriteString("\\usepackage{listings}\n")
+	out.WriteString("\\usepackage[margin=1in]{geometry}\n")
+	out.WriteString("\\usepackage[utf8]{inputenc}\n")
+	out.WriteString("\\usepackage{verbatim}\n")
+	out.WriteString("\\usepackage[normalem]{ulem}\n")
+	out.WriteString("\\usepackage{hyperref}\n")
+	out.WriteString("\n")
+	out.WriteString("\\hypersetup{colorlinks,%\n")
+	out.WriteString("  citecolor=black,%\n")
+	out.WriteString("  filecolor=black,%\n")
+	out.WriteString("  linkcolor=black,%\n")
+	out.WriteString("  urlcolor=black,%\n")
+	out.WriteString("  pdfstartview=FitH,%\n")
+	out.WriteString("  breaklinks=true,%\n")
+	out.WriteString("  pdfauthor={Blackfriday Markdown Processor v")
+	out.WriteString(VERSION)
+	out.WriteString("}}\n")
+	out.WriteString("\n")
+	out.WriteString("\\newcommand{\\HRule}{\\rule{\\linewidth}{0.5mm}}\n")
+	out.WriteString("\\addtolength{\\parskip}{0.5\\baselineskip}\n")
+	out.WriteString("\\parindent=0pt\n")
+	out.WriteString("\n")
+	out.WriteString("\\begin{document}\n")
+}
+
+func (options *Latex) DocumentFooter(out *bytes.Buffer) {
+	out.WriteString("\n\\end{document}\n")
+}
diff --git a/vendor/github.com/russross/blackfriday/markdown.go b/vendor/github.com/russross/blackfriday/markdown.go
new file mode 100644
index 00000000..1722a738
--- /dev/null
+++ b/vendor/github.com/russross/blackfriday/markdown.go
@@ -0,0 +1,931 @@
+//
+// Blackfriday Markdown Processor
+// Available at http://github.com/russross/blackfriday
+//
+// Copyright © 2011 Russ Ross <russ@russross.com>.
+// Distributed under the Simplified BSD License.
+// See README.md for details.
+//
+
+//
+//
+// Markdown parsing and processing
+//
+//
+
+package blackfriday
+
+import (
+	"bytes"
+	"fmt"
+	"strings"
+	"unicode/utf8"
+)
+
+const VERSION = "1.5"
+
+// These are the supported markdown parsing extensions.
+// OR these values together to select multiple extensions.
+const (
+	EXTENSION_NO_INTRA_EMPHASIS          = 1 << iota // ignore emphasis markers inside words
+	EXTENSION_TABLES                                 // render tables
+	EXTENSION_FENCED_CODE                            // render fenced code blocks
+	EXTENSION_AUTOLINK                               // detect embedded URLs that are not explicitly marked
+	EXTENSION_STRIKETHROUGH                          // strikethrough text using ~~test~~
+	EXTENSION_LAX_HTML_BLOCKS                        // loosen up HTML block parsing rules
+	EXTENSION_SPACE_HEADERS                          // be strict about prefix header rules
+	EXTENSION_HARD_LINE_BREAK                        // translate newlines into line breaks
+	EXTENSION_TAB_SIZE_EIGHT                         // expand tabs to eight spaces instead of four
+	EXTENSION_FOOTNOTES                              // Pandoc-style footnotes
+	EXTENSION_NO_EMPTY_LINE_BEFORE_BLOCK             // No need to insert an empty line to start a (code, quote, ordered list, unordered list) block
+	EXTENSION_HEADER_IDS                             // specify header IDs  with {#id}
+	EXTENSION_TITLEBLOCK                             // Titleblock ala pandoc
+	EXTENSION_AUTO_HEADER_IDS                        // Create the header ID from the text
+	EXTENSION_BACKSLASH_LINE_BREAK                   // translate trailing backslashes into line breaks
+	EXTENSION_DEFINITION_LISTS                       // render definition lists
+	EXTENSION_JOIN_LINES                             // delete newline and join lines
+
+	commonHtmlFlags = 0 |
+		HTML_USE_XHTML |
+		HTML_USE_SMARTYPANTS |
+		HTML_SMARTYPANTS_FRACTIONS |
+		HTML_SMARTYPANTS_DASHES |
+		HTML_SMARTYPANTS_LATEX_DASHES
+
+	commonExtensions = 0 |
+		EXTENSION_NO_INTRA_EMPHASIS |
+		EXTENSION_TABLES |
+		EXTENSION_FENCED_CODE |
+		EXTENSION_AUTOLINK |
+		EXTENSION_STRIKETHROUGH |
+		EXTENSION_SPACE_HEADERS |
+		EXTENSION_HEADER_IDS |
+		EXTENSION_BACKSLASH_LINE_BREAK |
+		EXTENSION_DEFINITION_LISTS
+)
+
+// These are the possible flag values for the link renderer.
+// Only a single one of these values will be used; they are not ORed together.
+// These are mostly of interest if you are writing a new output format.
+const (
+	LINK_TYPE_NOT_AUTOLINK = iota
+	LINK_TYPE_NORMAL
+	LINK_TYPE_EMAIL
+)
+
+// These are the possible flag values for the ListItem renderer.
+// Multiple flag values may be ORed together.
+// These are mostly of interest if you are writing a new output format.
+const (
+	LIST_TYPE_ORDERED = 1 << iota
+	LIST_TYPE_DEFINITION
+	LIST_TYPE_TERM
+	LIST_ITEM_CONTAINS_BLOCK
+	LIST_ITEM_BEGINNING_OF_LIST
+	LIST_ITEM_END_OF_LIST
+)
+
+// These are the possible flag values for the table cell renderer.
+// Only a single one of these values will be used; they are not ORed together.
+// These are mostly of interest if you are writing a new output format.
+const (
+	TABLE_ALIGNMENT_LEFT = 1 << iota
+	TABLE_ALIGNMENT_RIGHT
+	TABLE_ALIGNMENT_CENTER = (TABLE_ALIGNMENT_LEFT | TABLE_ALIGNMENT_RIGHT)
+)
+
+// The size of a tab stop.
+const (
+	TAB_SIZE_DEFAULT = 4
+	TAB_SIZE_EIGHT   = 8
+)
+
+// blockTags is a set of tags that are recognized as HTML block tags.
+// Any of these can be included in markdown text without special escaping.
+var blockTags = map[string]struct{}{
+	"blockquote": {},
+	"del":        {},
+	"div":        {},
+	"dl":         {},
+	"fieldset":   {},
+	"form":       {},
+	"h1":         {},
+	"h2":         {},
+	"h3":         {},
+	"h4":         {},
+	"h5":         {},
+	"h6":         {},
+	"iframe":     {},
+	"ins":        {},
+	"math":       {},
+	"noscript":   {},
+	"ol":         {},
+	"pre":        {},
+	"p":          {},
+	"script":     {},
+	"style":      {},
+	"table":      {},
+	"ul":         {},
+
+	// HTML5
+	"address":    {},
+	"article":    {},
+	"aside":      {},
+	"canvas":     {},
+	"figcaption": {},
+	"figure":     {},
+	"footer":     {},
+	"header":     {},
+	"hgroup":     {},
+	"main":       {},
+	"nav":        {},
+	"output":     {},
+	"progress":   {},
+	"section":    {},
+	"video":      {},
+}
+
+// Renderer is the rendering interface.
+// This is mostly of interest if you are implementing a new rendering format.
+//
+// When a byte slice is provided, it contains the (rendered) contents of the
+// element.
+//
+// When a callback is provided instead, it will write the contents of the
+// respective element directly to the output buffer and return true on success.
+// If the callback returns false, the rendering function should reset the
+// output buffer as though it had never been called.
+//
+// Currently Html and Latex implementations are provided
+type Renderer interface {
+	// block-level callbacks
+	BlockCode(out *bytes.Buffer, text []byte, lang string)
+	BlockQuote(out *bytes.Buffer, text []byte)
+	BlockHtml(out *bytes.Buffer, text []byte)
+	Header(out *bytes.Buffer, text func() bool, level int, id string)
+	HRule(out *bytes.Buffer)
+	List(out *bytes.Buffer, text func() bool, flags int)
+	ListItem(out *bytes.Buffer, text []byte, flags int)
+	Paragraph(out *bytes.Buffer, text func() bool)
+	Table(out *bytes.Buffer, header []byte, body []byte, columnData []int)
+	TableRow(out *bytes.Buffer, text []byte)
+	TableHeaderCell(out *bytes.Buffer, text []byte, flags int)
+	TableCell(out *bytes.Buffer, text []byte, flags int)
+	Footnotes(out *bytes.Buffer, text func() bool)
+	FootnoteItem(out *bytes.Buffer, name, text []byte, flags int)
+	TitleBlock(out *bytes.Buffer, text []byte)
+
+	// Span-level callbacks
+	AutoLink(out *bytes.Buffer, link []byte, kind int)
+	CodeSpan(out *bytes.Buffer, text []byte)
+	DoubleEmphasis(out *bytes.Buffer, text []byte)
+	Emphasis(out *bytes.Buffer, text []byte)
+	Image(out *bytes.Buffer, link []byte, title []byte, alt []byte)
+	LineBreak(out *bytes.Buffer)
+	Link(out *bytes.Buffer, link []byte, title []byte, content []byte)
+	RawHtmlTag(out *bytes.Buffer, tag []byte)
+	TripleEmphasis(out *bytes.Buffer, text []byte)
+	StrikeThrough(out *bytes.Buffer, text []byte)
+	FootnoteRef(out *bytes.Buffer, ref []byte, id int)
+
+	// Low-level callbacks
+	Entity(out *bytes.Buffer, entity []byte)
+	NormalText(out *bytes.Buffer, text []byte)
+
+	// Header and footer
+	DocumentHeader(out *bytes.Buffer)
+	DocumentFooter(out *bytes.Buffer)
+
+	GetFlags() int
+}
+
+// Callback functions for inline parsing. One such function is defined
+// for each character that triggers a response when parsing inline data.
+type inlineParser func(p *parser, out *bytes.Buffer, data []byte, offset int) int
+
+// Parser holds runtime state used by the parser.
+// This is constructed by the Markdown function.
+type parser struct {
+	r              Renderer
+	refOverride    ReferenceOverrideFunc
+	refs           map[string]*reference
+	inlineCallback [256]inlineParser
+	flags          int
+	nesting        int
+	maxNesting     int
+	insideLink     bool
+
+	// Footnotes need to be ordered as well as available to quickly check for
+	// presence. If a ref is also a footnote, it's stored both in refs and here
+	// in notes. Slice is nil if footnotes not enabled.
+	notes       []*reference
+	notesRecord map[string]struct{}
+}
+
+func (p *parser) getRef(refid string) (ref *reference, found bool) {
+	if p.refOverride != nil {
+		r, overridden := p.refOverride(refid)
+		if overridden {
+			if r == nil {
+				return nil, false
+			}
+			return &reference{
+				link:     []byte(r.Link),
+				title:    []byte(r.Title),
+				noteId:   0,
+				hasBlock: false,
+				text:     []byte(r.Text)}, true
+		}
+	}
+	// refs are case insensitive
+	ref, found = p.refs[strings.ToLower(refid)]
+	return ref, found
+}
+
+func (p *parser) isFootnote(ref *reference) bool {
+	_, ok := p.notesRecord[string(ref.link)]
+	return ok
+}
+
+//
+//
+// Public interface
+//
+//
+
+// Reference represents the details of a link.
+// See the documentation in Options for more details on use-case.
+type Reference struct {
+	// Link is usually the URL the reference points to.
+	Link string
+	// Title is the alternate text describing the link in more detail.
+	Title string
+	// Text is the optional text to override the ref with if the syntax used was
+	// [refid][]
+	Text string
+}
+
+// ReferenceOverrideFunc is expected to be called with a reference string and
+// return either a valid Reference type that the reference string maps to or
+// nil. If overridden is false, the default reference logic will be executed.
+// See the documentation in Options for more details on use-case.
+type ReferenceOverrideFunc func(reference string) (ref *Reference, overridden bool)
+
+// Options represents configurable overrides and callbacks (in addition to the
+// extension flag set) for configuring a Markdown parse.
+type Options struct {
+	// Extensions is a flag set of bit-wise ORed extension bits. See the
+	// EXTENSION_* flags defined in this package.
+	Extensions int
+
+	// ReferenceOverride is an optional function callback that is called every
+	// time a reference is resolved.
+	//
+	// In Markdown, the link reference syntax can be made to resolve a link to
+	// a reference instead of an inline URL, in one of the following ways:
+	//
+	//  * [link text][refid]
+	//  * [refid][]
+	//
+	// Usually, the refid is defined at the bottom of the Markdown document. If
+	// this override function is provided, the refid is passed to the override
+	// function first, before consulting the defined refids at the bottom. If
+	// the override function indicates an override did not occur, the refids at
+	// the bottom will be used to fill in the link details.
+	ReferenceOverride ReferenceOverrideFunc
+}
+
+// MarkdownBasic is a convenience function for simple rendering.
+// It processes markdown input with no extensions enabled.
+func MarkdownBasic(input []byte) []byte {
+	// set up the HTML renderer
+	htmlFlags := HTML_USE_XHTML
+	renderer := HtmlRenderer(htmlFlags, "", "")
+
+	// set up the parser
+	return MarkdownOptions(input, renderer, Options{Extensions: 0})
+}
+
+// Call Markdown with most useful extensions enabled
+// MarkdownCommon is a convenience function for simple rendering.
+// It processes markdown input with common extensions enabled, including:
+//
+// * Smartypants processing with smart fractions and LaTeX dashes
+//
+// * Intra-word emphasis suppression
+//
+// * Tables
+//
+// * Fenced code blocks
+//
+// * Autolinking
+//
+// * Strikethrough support
+//
+// * Strict header parsing
+//
+// * Custom Header IDs
+func MarkdownCommon(input []byte) []byte {
+	// set up the HTML renderer
+	renderer := HtmlRenderer(commonHtmlFlags, "", "")
+	return MarkdownOptions(input, renderer, Options{
+		Extensions: commonExtensions})
+}
+
+// Markdown is the main rendering function.
+// It parses and renders a block of markdown-encoded text.
+// The supplied Renderer is used to format the output, and extensions dictates
+// which non-standard extensions are enabled.
+//
+// To use the supplied Html or LaTeX renderers, see HtmlRenderer and
+// LatexRenderer, respectively.
+func Markdown(input []byte, renderer Renderer, extensions int) []byte {
+	return MarkdownOptions(input, renderer, Options{
+		Extensions: extensions})
+}
+
+// MarkdownOptions is just like Markdown but takes additional options through
+// the Options struct.
+func MarkdownOptions(input []byte, renderer Renderer, opts Options) []byte {
+	// no point in parsing if we can't render
+	if renderer == nil {
+		return nil
+	}
+
+	extensions := opts.Extensions
+
+	// fill in the render structure
+	p := new(parser)
+	p.r = renderer
+	p.flags = extensions
+	p.refOverride = opts.ReferenceOverride
+	p.refs = make(map[string]*reference)
+	p.maxNesting = 16
+	p.insideLink = false
+
+	// register inline parsers
+	p.inlineCallback['*'] = emphasis
+	p.inlineCallback['_'] = emphasis
+	if extensions&EXTENSION_STRIKETHROUGH != 0 {
+		p.inlineCallback['~'] = emphasis
+	}
+	p.inlineCallback['`'] = codeSpan
+	p.inlineCallback['\n'] = lineBreak
+	p.inlineCallback['['] = link
+	p.inlineCallback['<'] = leftAngle
+	p.inlineCallback['\\'] = escape
+	p.inlineCallback['&'] = entity
+
+	if extensions&EXTENSION_AUTOLINK != 0 {
+		p.inlineCallback[':'] = autoLink
+	}
+
+	if extensions&EXTENSION_FOOTNOTES != 0 {
+		p.notes = make([]*reference, 0)
+		p.notesRecord = make(map[string]struct{})
+	}
+
+	first := firstPass(p, input)
+	second := secondPass(p, first)
+	return second
+}
+
+// first pass:
+// - normalize newlines
+// - extract references (outside of fenced code blocks)
+// - expand tabs (outside of fenced code blocks)
+// - copy everything else
+func firstPass(p *parser, input []byte) []byte {
+	var out bytes.Buffer
+	tabSize := TAB_SIZE_DEFAULT
+	if p.flags&EXTENSION_TAB_SIZE_EIGHT != 0 {
+		tabSize = TAB_SIZE_EIGHT
+	}
+	beg := 0
+	lastFencedCodeBlockEnd := 0
+	for beg < len(input) {
+		// Find end of this line, then process the line.
+		end := beg
+		for end < len(input) && input[end] != '\n' && input[end] != '\r' {
+			end++
+		}
+
+		if p.flags&EXTENSION_FENCED_CODE != 0 {
+			// track fenced code block boundaries to suppress tab expansion
+			// and reference extraction inside them:
+			if beg >= lastFencedCodeBlockEnd {
+				if i := p.fencedCodeBlock(&out, input[beg:], false); i > 0 {
+					lastFencedCodeBlockEnd = beg + i
+				}
+			}
+		}
+
+		// add the line body if present
+		if end > beg {
+			if end < lastFencedCodeBlockEnd { // Do not expand tabs while inside fenced code blocks.
+				out.Write(input[beg:end])
+			} else if refEnd := isReference(p, input[beg:], tabSize); refEnd > 0 {
+				beg += refEnd
+				continue
+			} else {
+				expandTabs(&out, input[beg:end], tabSize)
+			}
+		}
+
+		if end < len(input) && input[end] == '\r' {
+			end++
+		}
+		if end < len(input) && input[end] == '\n' {
+			end++
+		}
+		out.WriteByte('\n')
+
+		beg = end
+	}
+
+	// empty input?
+	if out.Len() == 0 {
+		out.WriteByte('\n')
+	}
+
+	return out.Bytes()
+}
+
+// second pass: actual rendering
+func secondPass(p *parser, input []byte) []byte {
+	var output bytes.Buffer
+
+	p.r.DocumentHeader(&output)
+	p.block(&output, input)
+
+	if p.flags&EXTENSION_FOOTNOTES != 0 && len(p.notes) > 0 {
+		p.r.Footnotes(&output, func() bool {
+			flags := LIST_ITEM_BEGINNING_OF_LIST
+			for i := 0; i < len(p.notes); i += 1 {
+				ref := p.notes[i]
+				var buf bytes.Buffer
+				if ref.hasBlock {
+					flags |= LIST_ITEM_CONTAINS_BLOCK
+					p.block(&buf, ref.title)
+				} else {
+					p.inline(&buf, ref.title)
+				}
+				p.r.FootnoteItem(&output, ref.link, buf.Bytes(), flags)
+				flags &^= LIST_ITEM_BEGINNING_OF_LIST | LIST_ITEM_CONTAINS_BLOCK
+			}
+
+			return true
+		})
+	}
+
+	p.r.DocumentFooter(&output)
+
+	if p.nesting != 0 {
+		panic("Nesting level did not end at zero")
+	}
+
+	return output.Bytes()
+}
+
+//
+// Link references
+//
+// This section implements support for references that (usually) appear
+// as footnotes in a document, and can be referenced anywhere in the document.
+// The basic format is:
+//
+//    [1]: http://www.google.com/ "Google"
+//    [2]: http://www.github.com/ "Github"
+//
+// Anywhere in the document, the reference can be linked by referring to its
+// label, i.e., 1 and 2 in this example, as in:
+//
+//    This library is hosted on [Github][2], a git hosting site.
+//
+// Actual footnotes as specified in Pandoc and supported by some other Markdown
+// libraries such as php-markdown are also taken care of. They look like this:
+//
+//    This sentence needs a bit of further explanation.[^note]
+//
+//    [^note]: This is the explanation.
+//
+// Footnotes should be placed at the end of the document in an ordered list.
+// Inline footnotes such as:
+//
+//    Inline footnotes^[Not supported.] also exist.
+//
+// are not yet supported.
+
+// References are parsed and stored in this struct.
+type reference struct {
+	link     []byte
+	title    []byte
+	noteId   int // 0 if not a footnote ref
+	hasBlock bool
+	text     []byte
+}
+
+func (r *reference) String() string {
+	return fmt.Sprintf("{link: %q, title: %q, text: %q, noteId: %d, hasBlock: %v}",
+		r.link, r.title, r.text, r.noteId, r.hasBlock)
+}
+
+// Check whether or not data starts with a reference link.
+// If so, it is parsed and stored in the list of references
+// (in the render struct).
+// Returns the number of bytes to skip to move past it,
+// or zero if the first line is not a reference.
+func isReference(p *parser, data []byte, tabSize int) int {
+	// up to 3 optional leading spaces
+	if len(data) < 4 {
+		return 0
+	}
+	i := 0
+	for i < 3 && data[i] == ' ' {
+		i++
+	}
+
+	noteId := 0
+
+	// id part: anything but a newline between brackets
+	if data[i] != '[' {
+		return 0
+	}
+	i++
+	if p.flags&EXTENSION_FOOTNOTES != 0 {
+		if i < len(data) && data[i] == '^' {
+			// we can set it to anything here because the proper noteIds will
+			// be assigned later during the second pass. It just has to be != 0
+			noteId = 1
+			i++
+		}
+	}
+	idOffset := i
+	for i < len(data) && data[i] != '\n' && data[i] != '\r' && data[i] != ']' {
+		i++
+	}
+	if i >= len(data) || data[i] != ']' {
+		return 0
+	}
+	idEnd := i
+
+	// spacer: colon (space | tab)* newline? (space | tab)*
+	i++
+	if i >= len(data) || data[i] != ':' {
+		return 0
+	}
+	i++
+	for i < len(data) && (data[i] == ' ' || data[i] == '\t') {
+		i++
+	}
+	if i < len(data) && (data[i] == '\n' || data[i] == '\r') {
+		i++
+		if i < len(data) && data[i] == '\n' && data[i-1] == '\r' {
+			i++
+		}
+	}
+	for i < len(data) && (data[i] == ' ' || data[i] == '\t') {
+		i++
+	}
+	if i >= len(data) {
+		return 0
+	}
+
+	var (
+		linkOffset, linkEnd   int
+		titleOffset, titleEnd int
+		lineEnd               int
+		raw                   []byte
+		hasBlock              bool
+	)
+
+	if p.flags&EXTENSION_FOOTNOTES != 0 && noteId != 0 {
+		linkOffset, linkEnd, raw, hasBlock = scanFootnote(p, data, i, tabSize)
+		lineEnd = linkEnd
+	} else {
+		linkOffset, linkEnd, titleOffset, titleEnd, lineEnd = scanLinkRef(p, data, i)
+	}
+	if lineEnd == 0 {
+		return 0
+	}
+
+	// a valid ref has been found
+
+	ref := &reference{
+		noteId:   noteId,
+		hasBlock: hasBlock,
+	}
+
+	if noteId > 0 {
+		// reusing the link field for the id since footnotes don't have links
+		ref.link = data[idOffset:idEnd]
+		// if footnote, it's not really a title, it's the contained text
+		ref.title = raw
+	} else {
+		ref.link = data[linkOffset:linkEnd]
+		ref.title = data[titleOffset:titleEnd]
+	}
+
+	// id matches are case-insensitive
+	id := string(bytes.ToLower(data[idOffset:idEnd]))
+
+	p.refs[id] = ref
+
+	return lineEnd
+}
+
+func scanLinkRef(p *parser, data []byte, i int) (linkOffset, linkEnd, titleOffset, titleEnd, lineEnd int) {
+	// link: whitespace-free sequence, optionally between angle brackets
+	if data[i] == '<' {
+		i++
+	}
+	linkOffset = i
+	if i == len(data) {
+		return
+	}
+	for i < len(data) && data[i] != ' ' && data[i] != '\t' && data[i] != '\n' && data[i] != '\r' {
+		i++
+	}
+	linkEnd = i
+	if data[linkOffset] == '<' && data[linkEnd-1] == '>' {
+		linkOffset++
+		linkEnd--
+	}
+
+	// optional spacer: (space | tab)* (newline | '\'' | '"' | '(' )
+	for i < len(data) && (data[i] == ' ' || data[i] == '\t') {
+		i++
+	}
+	if i < len(data) && data[i] != '\n' && data[i] != '\r' && data[i] != '\'' && data[i] != '"' && data[i] != '(' {
+		return
+	}
+
+	// compute end-of-line
+	if i >= len(data) || data[i] == '\r' || data[i] == '\n' {
+		lineEnd = i
+	}
+	if i+1 < len(data) && data[i] == '\r' && data[i+1] == '\n' {
+		lineEnd++
+	}
+
+	// optional (space|tab)* spacer after a newline
+	if lineEnd > 0 {
+		i = lineEnd + 1
+		for i < len(data) && (data[i] == ' ' || data[i] == '\t') {
+			i++
+		}
+	}
+
+	// optional title: any non-newline sequence enclosed in '"() alone on its line
+	if i+1 < len(data) && (data[i] == '\'' || data[i] == '"' || data[i] == '(') {
+		i++
+		titleOffset = i
+
+		// look for EOL
+		for i < len(data) && data[i] != '\n' && data[i] != '\r' {
+			i++
+		}
+		if i+1 < len(data) && data[i] == '\n' && data[i+1] == '\r' {
+			titleEnd = i + 1
+		} else {
+			titleEnd = i
+		}
+
+		// step back
+		i--
+		for i > titleOffset && (data[i] == ' ' || data[i] == '\t') {
+			i--
+		}
+		if i > titleOffset && (data[i] == '\'' || data[i] == '"' || data[i] == ')') {
+			lineEnd = titleEnd
+			titleEnd = i
+		}
+	}
+
+	return
+}
+
+// The first bit of this logic is the same as (*parser).listItem, but the rest
+// is much simpler. This function simply finds the entire block and shifts it
+// over by one tab if it is indeed a block (just returns the line if it's not).
+// blockEnd is the end of the section in the input buffer, and contents is the
+// extracted text that was shifted over one tab. It will need to be rendered at
+// the end of the document.
+func scanFootnote(p *parser, data []byte, i, indentSize int) (blockStart, blockEnd int, contents []byte, hasBlock bool) {
+	if i == 0 || len(data) == 0 {
+		return
+	}
+
+	// skip leading whitespace on first line
+	for i < len(data) && data[i] == ' ' {
+		i++
+	}
+
+	blockStart = i
+
+	// find the end of the line
+	blockEnd = i
+	for i < len(data) && data[i-1] != '\n' {
+		i++
+	}
+
+	// get working buffer
+	var raw bytes.Buffer
+
+	// put the first line into the working buffer
+	raw.Write(data[blockEnd:i])
+	blockEnd = i
+
+	// process the following lines
+	containsBlankLine := false
+
+gatherLines:
+	for blockEnd < len(data) {
+		i++
+
+		// find the end of this line
+		for i < len(data) && data[i-1] != '\n' {
+			i++
+		}
+
+		// if it is an empty line, guess that it is part of this item
+		// and move on to the next line
+		if p.isEmpty(data[blockEnd:i]) > 0 {
+			containsBlankLine = true
+			blockEnd = i
+			continue
+		}
+
+		n := 0
+		if n = isIndented(data[blockEnd:i], indentSize); n == 0 {
+			// this is the end of the block.
+			// we don't want to include this last line in the index.
+			break gatherLines
+		}
+
+		// if there were blank lines before this one, insert a new one now
+		if containsBlankLine {
+			raw.WriteByte('\n')
+			containsBlankLine = false
+		}
+
+		// get rid of that first tab, write to buffer
+		raw.Write(data[blockEnd+n : i])
+		hasBlock = true
+
+		blockEnd = i
+	}
+
+	if data[blockEnd-1] != '\n' {
+		raw.WriteByte('\n')
+	}
+
+	contents = raw.Bytes()
+
+	return
+}
+
+//
+//
+// Miscellaneous helper functions
+//
+//
+
+// Test if a character is a punctuation symbol.
+// Taken from a private function in regexp in the stdlib.
+func ispunct(c byte) bool {
+	for _, r := range []byte("!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~") {
+		if c == r {
+			return true
+		}
+	}
+	return false
+}
+
+// Test if a character is a whitespace character.
+func isspace(c byte) bool {
+	return c == ' ' || c == '\t' || c == '\n' || c == '\r' || c == '\f' || c == '\v'
+}
+
+// Test if a character is letter.
+func isletter(c byte) bool {
+	return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z')
+}
+
+// Test if a character is a letter or a digit.
+// TODO: check when this is looking for ASCII alnum and when it should use unicode
+func isalnum(c byte) bool {
+	return (c >= '0' && c <= '9') || isletter(c)
+}
+
+// Replace tab characters with spaces, aligning to the next TAB_SIZE column.
+// always ends output with a newline
+func expandTabs(out *bytes.Buffer, line []byte, tabSize int) {
+	// first, check for common cases: no tabs, or only tabs at beginning of line
+	i, prefix := 0, 0
+	slowcase := false
+	for i = 0; i < len(line); i++ {
+		if line[i] == '\t' {
+			if prefix == i {
+				prefix++
+			} else {
+				slowcase = true
+				break
+			}
+		}
+	}
+
+	// no need to decode runes if all tabs are at the beginning of the line
+	if !slowcase {
+		for i = 0; i < prefix*tabSize; i++ {
+			out.WriteByte(' ')
+		}
+		out.Write(line[prefix:])
+		return
+	}
+
+	// the slow case: we need to count runes to figure out how
+	// many spaces to insert for each tab
+	column := 0
+	i = 0
+	for i < len(line) {
+		start := i
+		for i < len(line) && line[i] != '\t' {
+			_, size := utf8.DecodeRune(line[i:])
+			i += size
+			column++
+		}
+
+		if i > start {
+			out.Write(line[start:i])
+		}
+
+		if i >= len(line) {
+			break
+		}
+
+		for {
+			out.WriteByte(' ')
+			column++
+			if column%tabSize == 0 {
+				break
+			}
+		}
+
+		i++
+	}
+}
+
+// Find if a line counts as indented or not.
+// Returns number of characters the indent is (0 = not indented).
+func isIndented(data []byte, indentSize int) int {
+	if len(data) == 0 {
+		return 0
+	}
+	if data[0] == '\t' {
+		return 1
+	}
+	if len(data) < indentSize {
+		return 0
+	}
+	for i := 0; i < indentSize; i++ {
+		if data[i] != ' ' {
+			return 0
+		}
+	}
+	return indentSize
+}
+
+// Create a url-safe slug for fragments
+func slugify(in []byte) []byte {
+	if len(in) == 0 {
+		return in
+	}
+	out := make([]byte, 0, len(in))
+	sym := false
+
+	for _, ch := range in {
+		if isalnum(ch) {
+			sym = false
+			out = append(out, ch)
+		} else if sym {
+			continue
+		} else {
+			out = append(out, '-')
+			sym = true
+		}
+	}
+	var a, b int
+	var ch byte
+	for a, ch = range out {
+		if ch != '-' {
+			break
+		}
+	}
+	for b = len(out) - 1; b > 0; b-- {
+		if out[b] != '-' {
+			break
+		}
+	}
+	return out[a : b+1]
+}
diff --git a/vendor/github.com/russross/blackfriday/smartypants.go b/vendor/github.com/russross/blackfriday/smartypants.go
new file mode 100644
index 00000000..f25bd07d
--- /dev/null
+++ b/vendor/github.com/russross/blackfriday/smartypants.go
@@ -0,0 +1,430 @@
+//
+// Blackfriday Markdown Processor
+// Available at http://github.com/russross/blackfriday
+//
+// Copyright © 2011 Russ Ross <russ@russross.com>.
+// Distributed under the Simplified BSD License.
+// See README.md for details.
+//
+
+//
+//
+// SmartyPants rendering
+//
+//
+
+package blackfriday
+
+import (
+	"bytes"
+)
+
+type smartypantsData struct {
+	inSingleQuote bool
+	inDoubleQuote bool
+}
+
+func wordBoundary(c byte) bool {
+	return c == 0 || isspace(c) || ispunct(c)
+}
+
+func tolower(c byte) byte {
+	if c >= 'A' && c <= 'Z' {
+		return c - 'A' + 'a'
+	}
+	return c
+}
+
+func isdigit(c byte) bool {
+	return c >= '0' && c <= '9'
+}
+
+func smartQuoteHelper(out *bytes.Buffer, previousChar byte, nextChar byte, quote byte, isOpen *bool, addNBSP bool) bool {
+	// edge of the buffer is likely to be a tag that we don't get to see,
+	// so we treat it like text sometimes
+
+	// enumerate all sixteen possibilities for (previousChar, nextChar)
+	// each can be one of {0, space, punct, other}
+	switch {
+	case previousChar == 0 && nextChar == 0:
+		// context is not any help here, so toggle
+		*isOpen = !*isOpen
+	case isspace(previousChar) && nextChar == 0:
+		// [ "] might be [ "<code>foo...]
+		*isOpen = true
+	case ispunct(previousChar) && nextChar == 0:
+		// [!"] hmm... could be [Run!"] or [("<code>...]
+		*isOpen = false
+	case /* isnormal(previousChar) && */ nextChar == 0:
+		// [a"] is probably a close
+		*isOpen = false
+	case previousChar == 0 && isspace(nextChar):
+		// [" ] might be [...foo</code>" ]
+		*isOpen = false
+	case isspace(previousChar) && isspace(nextChar):
+		// [ " ] context is not any help here, so toggle
+		*isOpen = !*isOpen
+	case ispunct(previousChar) && isspace(nextChar):
+		// [!" ] is probably a close
+		*isOpen = false
+	case /* isnormal(previousChar) && */ isspace(nextChar):
+		// [a" ] this is one of the easy cases
+		*isOpen = false
+	case previousChar == 0 && ispunct(nextChar):
+		// ["!] hmm... could be ["$1.95] or [</code>"!...]
+		*isOpen = false
+	case isspace(previousChar) && ispunct(nextChar):
+		// [ "!] looks more like [ "$1.95]
+		*isOpen = true
+	case ispunct(previousChar) && ispunct(nextChar):
+		// [!"!] context is not any help here, so toggle
+		*isOpen = !*isOpen
+	case /* isnormal(previousChar) && */ ispunct(nextChar):
+		// [a"!] is probably a close
+		*isOpen = false
+	case previousChar == 0 /* && isnormal(nextChar) */ :
+		// ["a] is probably an open
+		*isOpen = true
+	case isspace(previousChar) /* && isnormal(nextChar) */ :
+		// [ "a] this is one of the easy cases
+		*isOpen = true
+	case ispunct(previousChar) /* && isnormal(nextChar) */ :
+		// [!"a] is probably an open
+		*isOpen = true
+	default:
+		// [a'b] maybe a contraction?
+		*isOpen = false
+	}
+
+	// Note that with the limited lookahead, this non-breaking
+	// space will also be appended to single double quotes.
+	if addNBSP && !*isOpen {
+		out.WriteString("&nbsp;")
+	}
+
+	out.WriteByte('&')
+	if *isOpen {
+		out.WriteByte('l')
+	} else {
+		out.WriteByte('r')
+	}
+	out.WriteByte(quote)
+	out.WriteString("quo;")
+
+	if addNBSP && *isOpen {
+		out.WriteString("&nbsp;")
+	}
+
+	return true
+}
+
+func smartSingleQuote(out *bytes.Buffer, smrt *smartypantsData, previousChar byte, text []byte) int {
+	if len(text) >= 2 {
+		t1 := tolower(text[1])
+
+		if t1 == '\'' {
+			nextChar := byte(0)
+			if len(text) >= 3 {
+				nextChar = text[2]
+			}
+			if smartQuoteHelper(out, previousChar, nextChar, 'd', &smrt.inDoubleQuote, false) {
+				return 1
+			}
+		}
+
+		if (t1 == 's' || t1 == 't' || t1 == 'm' || t1 == 'd') && (len(text) < 3 || wordBoundary(text[2])) {
+			out.WriteString("&rsquo;")
+			return 0
+		}
+
+		if len(text) >= 3 {
+			t2 := tolower(text[2])
+
+			if ((t1 == 'r' && t2 == 'e') || (t1 == 'l' && t2 == 'l') || (t1 == 'v' && t2 == 'e')) &&
+				(len(text) < 4 || wordBoundary(text[3])) {
+				out.WriteString("&rsquo;")
+				return 0
+			}
+		}
+	}
+
+	nextChar := byte(0)
+	if len(text) > 1 {
+		nextChar = text[1]
+	}
+	if smartQuoteHelper(out, previousChar, nextChar, 's', &smrt.inSingleQuote, false) {
+		return 0
+	}
+
+	out.WriteByte(text[0])
+	return 0
+}
+
+func smartParens(out *bytes.Buffer, smrt *smartypantsData, previousChar byte, text []byte) int {
+	if len(text) >= 3 {
+		t1 := tolower(text[1])
+		t2 := tolower(text[2])
+
+		if t1 == 'c' && t2 == ')' {
+			out.WriteString("&copy;")
+			return 2
+		}
+
+		if t1 == 'r' && t2 == ')' {
+			out.WriteString("&reg;")
+			return 2
+		}
+
+		if len(text) >= 4 && t1 == 't' && t2 == 'm' && text[3] == ')' {
+			out.WriteString("&trade;")
+			return 3
+		}
+	}
+
+	out.WriteByte(text[0])
+	return 0
+}
+
+func smartDash(out *bytes.Buffer, smrt *smartypantsData, previousChar byte, text []byte) int {
+	if len(text) >= 2 {
+		if text[1] == '-' {
+			out.WriteString("&mdash;")
+			return 1
+		}
+
+		if wordBoundary(previousChar) && wordBoundary(text[1]) {
+			out.WriteString("&ndash;")
+			return 0
+		}
+	}
+
+	out.WriteByte(text[0])
+	return 0
+}
+
+func smartDashLatex(out *bytes.Buffer, smrt *smartypantsData, previousChar byte, text []byte) int {
+	if len(text) >= 3 && text[1] == '-' && text[2] == '-' {
+		out.WriteString("&mdash;")
+		return 2
+	}
+	if len(text) >= 2 && text[1] == '-' {
+		out.WriteString("&ndash;")
+		return 1
+	}
+
+	out.WriteByte(text[0])
+	return 0
+}
+
+func smartAmpVariant(out *bytes.Buffer, smrt *smartypantsData, previousChar byte, text []byte, quote byte, addNBSP bool) int {
+	if bytes.HasPrefix(text, []byte("&quot;")) {
+		nextChar := byte(0)
+		if len(text) >= 7 {
+			nextChar = text[6]
+		}
+		if smartQuoteHelper(out, previousChar, nextChar, quote, &smrt.inDoubleQuote, addNBSP) {
+			return 5
+		}
+	}
+
+	if bytes.HasPrefix(text, []byte("&#0;")) {
+		return 3
+	}
+
+	out.WriteByte('&')
+	return 0
+}
+
+func smartAmp(angledQuotes, addNBSP bool) func(out *bytes.Buffer, smrt *smartypantsData, previousChar byte, text []byte) int {
+	var quote byte = 'd'
+	if angledQuotes {
+		quote = 'a'
+	}
+
+	return func(out *bytes.Buffer, smrt *smartypantsData, previousChar byte, text []byte) int {
+		return smartAmpVariant(out, smrt, previousChar, text, quote, addNBSP)
+	}
+}
+
+func smartPeriod(out *bytes.Buffer, smrt *smartypantsData, previousChar byte, text []byte) int {
+	if len(text) >= 3 && text[1] == '.' && text[2] == '.' {
+		out.WriteString("&hellip;")
+		return 2
+	}
+
+	if len(text) >= 5 && text[1] == ' ' && text[2] == '.' && text[3] == ' ' && text[4] == '.' {
+		out.WriteString("&hellip;")
+		return 4
+	}
+
+	out.WriteByte(text[0])
+	return 0
+}
+
+func smartBacktick(out *bytes.Buffer, smrt *smartypantsData, previousChar byte, text []byte) int {
+	if len(text) >= 2 && text[1] == '`' {
+		nextChar := byte(0)
+		if len(text) >= 3 {
+			nextChar = text[2]
+		}
+		if smartQuoteHelper(out, previousChar, nextChar, 'd', &smrt.inDoubleQuote, false) {
+			return 1
+		}
+	}
+
+	out.WriteByte(text[0])
+	return 0
+}
+
+func smartNumberGeneric(out *bytes.Buffer, smrt *smartypantsData, previousChar byte, text []byte) int {
+	if wordBoundary(previousChar) && previousChar != '/' && len(text) >= 3 {
+		// is it of the form digits/digits(word boundary)?, i.e., \d+/\d+\b
+		// note: check for regular slash (/) or fraction slash (⁄, 0x2044, or 0xe2 81 84 in utf-8)
+		//       and avoid changing dates like 1/23/2005 into fractions.
+		numEnd := 0
+		for len(text) > numEnd && isdigit(text[numEnd]) {
+			numEnd++
+		}
+		if numEnd == 0 {
+			out.WriteByte(text[0])
+			return 0
+		}
+		denStart := numEnd + 1
+		if len(text) > numEnd+3 && text[numEnd] == 0xe2 && text[numEnd+1] == 0x81 && text[numEnd+2] == 0x84 {
+			denStart = numEnd + 3
+		} else if len(text) < numEnd+2 || text[numEnd] != '/' {
+			out.WriteByte(text[0])
+			return 0
+		}
+		denEnd := denStart
+		for len(text) > denEnd && isdigit(text[denEnd]) {
+			denEnd++
+		}
+		if denEnd == denStart {
+			out.WriteByte(text[0])
+			return 0
+		}
+		if len(text) == denEnd || wordBoundary(text[denEnd]) && text[denEnd] != '/' {
+			out.WriteString("<sup>")
+			out.Write(text[:numEnd])
+			out.WriteString("</sup>&frasl;<sub>")
+			out.Write(text[denStart:denEnd])
+			out.WriteString("</sub>")
+			return denEnd - 1
+		}
+	}
+
+	out.WriteByte(text[0])
+	return 0
+}
+
+func smartNumber(out *bytes.Buffer, smrt *smartypantsData, previousChar byte, text []byte) int {
+	if wordBoundary(previousChar) && previousChar != '/' && len(text) >= 3 {
+		if text[0] == '1' && text[1] == '/' && text[2] == '2' {
+			if len(text) < 4 || wordBoundary(text[3]) && text[3] != '/' {
+				out.WriteString("&frac12;")
+				return 2
+			}
+		}
+
+		if text[0] == '1' && text[1] == '/' && text[2] == '4' {
+			if len(text) < 4 || wordBoundary(text[3]) && text[3] != '/' || (len(text) >= 5 && tolower(text[3]) == 't' && tolower(text[4]) == 'h') {
+				out.WriteString("&frac14;")
+				return 2
+			}
+		}
+
+		if text[0] == '3' && text[1] == '/' && text[2] == '4' {
+			if len(text) < 4 || wordBoundary(text[3]) && text[3] != '/' || (len(text) >= 6 && tolower(text[3]) == 't' && tolower(text[4]) == 'h' && tolower(text[5]) == 's') {
+				out.WriteString("&frac34;")
+				return 2
+			}
+		}
+	}
+
+	out.WriteByte(text[0])
+	return 0
+}
+
+func smartDoubleQuoteVariant(out *bytes.Buffer, smrt *smartypantsData, previousChar byte, text []byte, quote byte) int {
+	nextChar := byte(0)
+	if len(text) > 1 {
+		nextChar = text[1]
+	}
+	if !smartQuoteHelper(out, previousChar, nextChar, quote, &smrt.inDoubleQuote, false) {
+		out.WriteString("&quot;")
+	}
+
+	return 0
+}
+
+func smartDoubleQuote(out *bytes.Buffer, smrt *smartypantsData, previousChar byte, text []byte) int {
+	return smartDoubleQuoteVariant(out, smrt, previousChar, text, 'd')
+}
+
+func smartAngledDoubleQuote(out *bytes.Buffer, smrt *smartypantsData, previousChar byte, text []byte) int {
+	return smartDoubleQuoteVariant(out, smrt, previousChar, text, 'a')
+}
+
+func smartLeftAngle(out *bytes.Buffer, smrt *smartypantsData, previousChar byte, text []byte) int {
+	i := 0
+
+	for i < len(text) && text[i] != '>' {
+		i++
+	}
+
+	out.Write(text[:i+1])
+	return i
+}
+
+type smartCallback func(out *bytes.Buffer, smrt *smartypantsData, previousChar byte, text []byte) int
+
+type smartypantsRenderer [256]smartCallback
+
+var (
+	smartAmpAngled      = smartAmp(true, false)
+	smartAmpAngledNBSP  = smartAmp(true, true)
+	smartAmpRegular     = smartAmp(false, false)
+	smartAmpRegularNBSP = smartAmp(false, true)
+)
+
+func smartypants(flags int) *smartypantsRenderer {
+	r := new(smartypantsRenderer)
+	addNBSP := flags&HTML_SMARTYPANTS_QUOTES_NBSP != 0
+	if flags&HTML_SMARTYPANTS_ANGLED_QUOTES == 0 {
+		r['"'] = smartDoubleQuote
+		if !addNBSP {
+			r['&'] = smartAmpRegular
+		} else {
+			r['&'] = smartAmpRegularNBSP
+		}
+	} else {
+		r['"'] = smartAngledDoubleQuote
+		if !addNBSP {
+			r['&'] = smartAmpAngled
+		} else {
+			r['&'] = smartAmpAngledNBSP
+		}
+	}
+	r['\''] = smartSingleQuote
+	r['('] = smartParens
+	if flags&HTML_SMARTYPANTS_DASHES != 0 {
+		if flags&HTML_SMARTYPANTS_LATEX_DASHES == 0 {
+			r['-'] = smartDash
+		} else {
+			r['-'] = smartDashLatex
+		}
+	}
+	r['.'] = smartPeriod
+	if flags&HTML_SMARTYPANTS_FRACTIONS == 0 {
+		r['1'] = smartNumber
+		r['3'] = smartNumber
+	} else {
+		for ch := '1'; ch <= '9'; ch++ {
+			r[ch] = smartNumberGeneric
+		}
+	}
+	r['<'] = smartLeftAngle
+	r['`'] = smartBacktick
+	return r
+}
diff --git a/vendor/github.com/spf13/cobra/doc/man_docs.go b/vendor/github.com/spf13/cobra/doc/man_docs.go
new file mode 100644
index 00000000..baa48118
--- /dev/null
+++ b/vendor/github.com/spf13/cobra/doc/man_docs.go
@@ -0,0 +1,236 @@
+// Copyright 2015 Red Hat Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package doc
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+	"time"
+
+	"github.com/cpuguy83/go-md2man/md2man"
+	"github.com/spf13/cobra"
+	"github.com/spf13/pflag"
+)
+
+// GenManTree will generate a man page for this command and all descendants
+// in the directory given. The header may be nil. This function may not work
+// correctly if your command names have `-` in them. If you have `cmd` with two
+// subcmds, `sub` and `sub-third`, and `sub` has a subcommand called `third`
+// it is undefined which help output will be in the file `cmd-sub-third.1`.
+func GenManTree(cmd *cobra.Command, header *GenManHeader, dir string) error {
+	return GenManTreeFromOpts(cmd, GenManTreeOptions{
+		Header:           header,
+		Path:             dir,
+		CommandSeparator: "-",
+	})
+}
+
+// GenManTreeFromOpts generates a man page for the command and all descendants.
+// The pages are written to the opts.Path directory.
+func GenManTreeFromOpts(cmd *cobra.Command, opts GenManTreeOptions) error {
+	header := opts.Header
+	if header == nil {
+		header = &GenManHeader{}
+	}
+	for _, c := range cmd.Commands() {
+		if !c.IsAvailableCommand() || c.IsAdditionalHelpTopicCommand() {
+			continue
+		}
+		if err := GenManTreeFromOpts(c, opts); err != nil {
+			return err
+		}
+	}
+	section := "1"
+	if header.Section != "" {
+		section = header.Section
+	}
+
+	separator := "_"
+	if opts.CommandSeparator != "" {
+		separator = opts.CommandSeparator
+	}
+	basename := strings.Replace(cmd.CommandPath(), " ", separator, -1)
+	filename := filepath.Join(opts.Path, basename+"."+section)
+	f, err := os.Create(filename)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	headerCopy := *header
+	return GenMan(cmd, &headerCopy, f)
+}
+
+// GenManTreeOptions is the options for generating the man pages.
+// Used only in GenManTreeFromOpts.
+type GenManTreeOptions struct {
+	Header           *GenManHeader
+	Path             string
+	CommandSeparator string
+}
+
+// GenManHeader is a lot like the .TH header at the start of man pages. These
+// include the title, section, date, source, and manual. We will use the
+// current time if Date if unset and will use "Auto generated by spf13/cobra"
+// if the Source is unset.
+type GenManHeader struct {
+	Title   string
+	Section string
+	Date    *time.Time
+	date    string
+	Source  string
+	Manual  string
+}
+
+// GenMan will generate a man page for the given command and write it to
+// w. The header argument may be nil, however obviously w may not.
+func GenMan(cmd *cobra.Command, header *GenManHeader, w io.Writer) error {
+	if header == nil {
+		header = &GenManHeader{}
+	}
+	fillHeader(header, cmd.CommandPath())
+
+	b := genMan(cmd, header)
+	_, err := w.Write(md2man.Render(b))
+	return err
+}
+
+func fillHeader(header *GenManHeader, name string) {
+	if header.Title == "" {
+		header.Title = strings.ToUpper(strings.Replace(name, " ", "\\-", -1))
+	}
+	if header.Section == "" {
+		header.Section = "1"
+	}
+	if header.Date == nil {
+		now := time.Now()
+		header.Date = &now
+	}
+	header.date = (*header.Date).Format("Jan 2006")
+	if header.Source == "" {
+		header.Source = "Auto generated by spf13/cobra"
+	}
+}
+
+func manPreamble(buf *bytes.Buffer, header *GenManHeader, cmd *cobra.Command, dashedName string) {
+	description := cmd.Long
+	if len(description) == 0 {
+		description = cmd.Short
+	}
+
+	buf.WriteString(fmt.Sprintf(`%% %s(%s)%s
+%% %s
+%% %s
+# NAME
+`, header.Title, header.Section, header.date, header.Source, header.Manual))
+	buf.WriteString(fmt.Sprintf("%s \\- %s\n\n", dashedName, cmd.Short))
+	buf.WriteString("# SYNOPSIS\n")
+	buf.WriteString(fmt.Sprintf("**%s**\n\n", cmd.UseLine()))
+	buf.WriteString("# DESCRIPTION\n")
+	buf.WriteString(description + "\n\n")
+}
+
+func manPrintFlags(buf *bytes.Buffer, flags *pflag.FlagSet) {
+	flags.VisitAll(func(flag *pflag.Flag) {
+		if len(flag.Deprecated) > 0 || flag.Hidden {
+			return
+		}
+		format := ""
+		if len(flag.Shorthand) > 0 && len(flag.ShorthandDeprecated) == 0 {
+			format = fmt.Sprintf("**-%s**, **--%s**", flag.Shorthand, flag.Name)
+		} else {
+			format = fmt.Sprintf("**--%s**", flag.Name)
+		}
+		if len(flag.NoOptDefVal) > 0 {
+			format += "["
+		}
+		if flag.Value.Type() == "string" {
+			// put quotes on the value
+			format += "=%q"
+		} else {
+			format += "=%s"
+		}
+		if len(flag.NoOptDefVal) > 0 {
+			format += "]"
+		}
+		format += "\n\t%s\n\n"
+		buf.WriteString(fmt.Sprintf(format, flag.DefValue, flag.Usage))
+	})
+}
+
+func manPrintOptions(buf *bytes.Buffer, command *cobra.Command) {
+	flags := command.NonInheritedFlags()
+	if flags.HasAvailableFlags() {
+		buf.WriteString("# OPTIONS\n")
+		manPrintFlags(buf, flags)
+		buf.WriteString("\n")
+	}
+	flags = command.InheritedFlags()
+	if flags.HasAvailableFlags() {
+		buf.WriteString("# OPTIONS INHERITED FROM PARENT COMMANDS\n")
+		manPrintFlags(buf, flags)
+		buf.WriteString("\n")
+	}
+}
+
+func genMan(cmd *cobra.Command, header *GenManHeader) []byte {
+	cmd.InitDefaultHelpCmd()
+	cmd.InitDefaultHelpFlag()
+
+	// something like `rootcmd-subcmd1-subcmd2`
+	dashCommandName := strings.Replace(cmd.CommandPath(), " ", "-", -1)
+
+	buf := new(bytes.Buffer)
+
+	manPreamble(buf, header, cmd, dashCommandName)
+	manPrintOptions(buf, cmd)
+	if len(cmd.Example) > 0 {
+		buf.WriteString("# EXAMPLE\n")
+		buf.WriteString(fmt.Sprintf("```\n%s\n```\n", cmd.Example))
+	}
+	if hasSeeAlso(cmd) {
+		buf.WriteString("# SEE ALSO\n")
+		seealsos := make([]string, 0)
+		if cmd.HasParent() {
+			parentPath := cmd.Parent().CommandPath()
+			dashParentPath := strings.Replace(parentPath, " ", "-", -1)
+			seealso := fmt.Sprintf("**%s(%s)**", dashParentPath, header.Section)
+			seealsos = append(seealsos, seealso)
+			cmd.VisitParents(func(c *cobra.Command) {
+				if c.DisableAutoGenTag {
+					cmd.DisableAutoGenTag = c.DisableAutoGenTag
+				}
+			})
+		}
+		children := cmd.Commands()
+		sort.Sort(byName(children))
+		for _, c := range children {
+			if !c.IsAvailableCommand() || c.IsAdditionalHelpTopicCommand() {
+				continue
+			}
+			seealso := fmt.Sprintf("**%s-%s(%s)**", dashCommandName, c.Name(), header.Section)
+			seealsos = append(seealsos, seealso)
+		}
+		buf.WriteString(strings.Join(seealsos, ", ") + "\n")
+	}
+	if !cmd.DisableAutoGenTag {
+		buf.WriteString(fmt.Sprintf("# HISTORY\n%s Auto generated by spf13/cobra\n", header.Date.Format("2-Jan-2006")))
+	}
+	return buf.Bytes()
+}
diff --git a/vendor/github.com/spf13/cobra/doc/man_docs.md b/vendor/github.com/spf13/cobra/doc/man_docs.md
new file mode 100644
index 00000000..3709160f
--- /dev/null
+++ b/vendor/github.com/spf13/cobra/doc/man_docs.md
@@ -0,0 +1,31 @@
+# Generating Man Pages For Your Own cobra.Command
+
+Generating man pages from a cobra command is incredibly easy. An example is as follows:
+
+```go
+package main
+
+import (
+	"log"
+
+	"github.com/spf13/cobra"
+	"github.com/spf13/cobra/doc"
+)
+
+func main() {
+	cmd := &cobra.Command{
+		Use:   "test",
+		Short: "my test program",
+	}
+	header := &doc.GenManHeader{
+		Title: "MINE",
+		Section: "3",
+	}
+	err := doc.GenManTree(cmd, header, "/tmp")
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+```
+
+That will get you a man page `/tmp/test.3`
diff --git a/vendor/github.com/spf13/cobra/doc/md_docs.go b/vendor/github.com/spf13/cobra/doc/md_docs.go
new file mode 100644
index 00000000..d76f6d5e
--- /dev/null
+++ b/vendor/github.com/spf13/cobra/doc/md_docs.go
@@ -0,0 +1,159 @@
+//Copyright 2015 Red Hat Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package doc
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+	"time"
+
+	"github.com/spf13/cobra"
+)
+
+func printOptions(buf *bytes.Buffer, cmd *cobra.Command, name string) error {
+	flags := cmd.NonInheritedFlags()
+	flags.SetOutput(buf)
+	if flags.HasAvailableFlags() {
+		buf.WriteString("### Options\n\n```\n")
+		flags.PrintDefaults()
+		buf.WriteString("```\n\n")
+	}
+
+	parentFlags := cmd.InheritedFlags()
+	parentFlags.SetOutput(buf)
+	if parentFlags.HasAvailableFlags() {
+		buf.WriteString("### Options inherited from parent commands\n\n```\n")
+		parentFlags.PrintDefaults()
+		buf.WriteString("```\n\n")
+	}
+	return nil
+}
+
+// GenMarkdown creates markdown output.
+func GenMarkdown(cmd *cobra.Command, w io.Writer) error {
+	return GenMarkdownCustom(cmd, w, func(s string) string { return s })
+}
+
+// GenMarkdownCustom creates custom markdown output.
+func GenMarkdownCustom(cmd *cobra.Command, w io.Writer, linkHandler func(string) string) error {
+	cmd.InitDefaultHelpCmd()
+	cmd.InitDefaultHelpFlag()
+
+	buf := new(bytes.Buffer)
+	name := cmd.CommandPath()
+
+	short := cmd.Short
+	long := cmd.Long
+	if len(long) == 0 {
+		long = short
+	}
+
+	buf.WriteString("## " + name + "\n\n")
+	buf.WriteString(short + "\n\n")
+	buf.WriteString("### Synopsis\n\n")
+	buf.WriteString(long + "\n\n")
+
+	if cmd.Runnable() {
+		buf.WriteString(fmt.Sprintf("```\n%s\n```\n\n", cmd.UseLine()))
+	}
+
+	if len(cmd.Example) > 0 {
+		buf.WriteString("### Examples\n\n")
+		buf.WriteString(fmt.Sprintf("```\n%s\n```\n\n", cmd.Example))
+	}
+
+	if err := printOptions(buf, cmd, name); err != nil {
+		return err
+	}
+	if hasSeeAlso(cmd) {
+		buf.WriteString("### SEE ALSO\n\n")
+		if cmd.HasParent() {
+			parent := cmd.Parent()
+			pname := parent.CommandPath()
+			link := pname + ".md"
+			link = strings.Replace(link, " ", "_", -1)
+			buf.WriteString(fmt.Sprintf("* [%s](%s)\t - %s\n", pname, linkHandler(link), parent.Short))
+			cmd.VisitParents(func(c *cobra.Command) {
+				if c.DisableAutoGenTag {
+					cmd.DisableAutoGenTag = c.DisableAutoGenTag
+				}
+			})
+		}
+
+		children := cmd.Commands()
+		sort.Sort(byName(children))
+
+		for _, child := range children {
+			if !child.IsAvailableCommand() || child.IsAdditionalHelpTopicCommand() {
+				continue
+			}
+			cname := name + " " + child.Name()
+			link := cname + ".md"
+			link = strings.Replace(link, " ", "_", -1)
+			buf.WriteString(fmt.Sprintf("* [%s](%s)\t - %s\n", cname, linkHandler(link), child.Short))
+		}
+		buf.WriteString("\n")
+	}
+	if !cmd.DisableAutoGenTag {
+		buf.WriteString("###### Auto generated by spf13/cobra on " + time.Now().Format("2-Jan-2006") + "\n")
+	}
+	_, err := buf.WriteTo(w)
+	return err
+}
+
+// GenMarkdownTree will generate a markdown page for this command and all
+// descendants in the directory given. The header may be nil.
+// This function may not work correctly if your command names have `-` in them.
+// If you have `cmd` with two subcmds, `sub` and `sub-third`,
+// and `sub` has a subcommand called `third`, it is undefined which
+// help output will be in the file `cmd-sub-third.1`.
+func GenMarkdownTree(cmd *cobra.Command, dir string) error {
+	identity := func(s string) string { return s }
+	emptyStr := func(s string) string { return "" }
+	return GenMarkdownTreeCustom(cmd, dir, emptyStr, identity)
+}
+
+// GenMarkdownTreeCustom is the the same as GenMarkdownTree, but
+// with custom filePrepender and linkHandler.
+func GenMarkdownTreeCustom(cmd *cobra.Command, dir string, filePrepender, linkHandler func(string) string) error {
+	for _, c := range cmd.Commands() {
+		if !c.IsAvailableCommand() || c.IsAdditionalHelpTopicCommand() {
+			continue
+		}
+		if err := GenMarkdownTreeCustom(c, dir, filePrepender, linkHandler); err != nil {
+			return err
+		}
+	}
+
+	basename := strings.Replace(cmd.CommandPath(), " ", "_", -1) + ".md"
+	filename := filepath.Join(dir, basename)
+	f, err := os.Create(filename)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	if _, err := io.WriteString(f, filePrepender(filename)); err != nil {
+		return err
+	}
+	if err := GenMarkdownCustom(cmd, f, linkHandler); err != nil {
+		return err
+	}
+	return nil
+}
diff --git a/vendor/github.com/spf13/cobra/doc/md_docs.md b/vendor/github.com/spf13/cobra/doc/md_docs.md
new file mode 100644
index 00000000..56ce9fe8
--- /dev/null
+++ b/vendor/github.com/spf13/cobra/doc/md_docs.md
@@ -0,0 +1,115 @@
+# Generating Markdown Docs For Your Own cobra.Command
+
+Generating man pages from a cobra command is incredibly easy. An example is as follows:
+
+```go
+package main
+
+import (
+	"log"
+
+	"github.com/spf13/cobra"
+	"github.com/spf13/cobra/doc"
+)
+
+func main() {
+	cmd := &cobra.Command{
+		Use:   "test",
+		Short: "my test program",
+	}
+	err := doc.GenMarkdownTree(cmd, "/tmp")
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+```
+
+That will get you a Markdown document `/tmp/test.md`
+
+## Generate markdown docs for the entire command tree
+
+This program can actually generate docs for the kubectl command in the kubernetes project
+
+```go
+package main
+
+import (
+	"log"
+	"io/ioutil"
+	"os"
+
+	"k8s.io/kubernetes/pkg/kubectl/cmd"
+	cmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"
+
+	"github.com/spf13/cobra/doc"
+)
+
+func main() {
+	kubectl := cmd.NewKubectlCommand(cmdutil.NewFactory(nil), os.Stdin, ioutil.Discard, ioutil.Discard)
+	err := doc.GenMarkdownTree(kubectl, "./")
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+```
+
+This will generate a whole series of files, one for each command in the tree, in the directory specified (in this case "./")
+
+## Generate markdown docs for a single command
+
+You may wish to have more control over the output, or only generate for a single command, instead of the entire command tree. If this is the case you may prefer to `GenMarkdown` instead of `GenMarkdownTree`
+
+```go
+	out := new(bytes.Buffer)
+	err := doc.GenMarkdown(cmd, out)
+	if err != nil {
+		log.Fatal(err)
+	}
+```
+
+This will write the markdown doc for ONLY "cmd" into the out, buffer.
+
+## Customize the output
+
+Both `GenMarkdown` and `GenMarkdownTree` have alternate versions with callbacks to get some control of the output:
+
+```go
+func GenMarkdownTreeCustom(cmd *Command, dir string, filePrepender, linkHandler func(string) string) error {
+	//...
+}
+```
+
+```go
+func GenMarkdownCustom(cmd *Command, out *bytes.Buffer, linkHandler func(string) string) error {
+	//...
+}
+```
+
+The `filePrepender` will prepend the return value given the full filepath to the rendered Markdown file. A common use case is to add front matter to use the generated documentation with [Hugo](http://gohugo.io/):
+
+```go
+const fmTemplate = `---
+date: %s
+title: "%s"
+slug: %s
+url: %s
+---
+`
+
+filePrepender := func(filename string) string {
+	now := time.Now().Format(time.RFC3339)
+	name := filepath.Base(filename)
+	base := strings.TrimSuffix(name, path.Ext(name))
+	url := "/commands/" + strings.ToLower(base) + "/"
+	return fmt.Sprintf(fmTemplate, now, strings.Replace(base, "_", " ", -1), base, url)
+}
+```
+
+The `linkHandler` can be used to customize the rendered internal links to the commands, given a filename:
+
+```go
+linkHandler := func(name string) string {
+	base := strings.TrimSuffix(name, path.Ext(name))
+	return "/commands/" + strings.ToLower(base) + "/"
+}
+```
diff --git a/vendor/github.com/spf13/cobra/doc/rest_docs.go b/vendor/github.com/spf13/cobra/doc/rest_docs.go
new file mode 100644
index 00000000..051d8dc8
--- /dev/null
+++ b/vendor/github.com/spf13/cobra/doc/rest_docs.go
@@ -0,0 +1,185 @@
+//Copyright 2015 Red Hat Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package doc
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+	"time"
+
+	"github.com/spf13/cobra"
+)
+
+func printOptionsReST(buf *bytes.Buffer, cmd *cobra.Command, name string) error {
+	flags := cmd.NonInheritedFlags()
+	flags.SetOutput(buf)
+	if flags.HasAvailableFlags() {
+		buf.WriteString("Options\n")
+		buf.WriteString("~~~~~~~\n\n::\n\n")
+		flags.PrintDefaults()
+		buf.WriteString("\n")
+	}
+
+	parentFlags := cmd.InheritedFlags()
+	parentFlags.SetOutput(buf)
+	if parentFlags.HasAvailableFlags() {
+		buf.WriteString("Options inherited from parent commands\n")
+		buf.WriteString("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n\n::\n\n")
+		parentFlags.PrintDefaults()
+		buf.WriteString("\n")
+	}
+	return nil
+}
+
+// linkHandler for default ReST hyperlink markup
+func defaultLinkHandler(name, ref string) string {
+	return fmt.Sprintf("`%s <%s.rst>`_", name, ref)
+}
+
+// GenReST creates reStructured Text output.
+func GenReST(cmd *cobra.Command, w io.Writer) error {
+	return GenReSTCustom(cmd, w, defaultLinkHandler)
+}
+
+// GenReSTCustom creates custom reStructured Text output.
+func GenReSTCustom(cmd *cobra.Command, w io.Writer, linkHandler func(string, string) string) error {
+	cmd.InitDefaultHelpCmd()
+	cmd.InitDefaultHelpFlag()
+
+	buf := new(bytes.Buffer)
+	name := cmd.CommandPath()
+
+	short := cmd.Short
+	long := cmd.Long
+	if len(long) == 0 {
+		long = short
+	}
+	ref := strings.Replace(name, " ", "_", -1)
+
+	buf.WriteString(".. _" + ref + ":\n\n")
+	buf.WriteString(name + "\n")
+	buf.WriteString(strings.Repeat("-", len(name)) + "\n\n")
+	buf.WriteString(short + "\n\n")
+	buf.WriteString("Synopsis\n")
+	buf.WriteString("~~~~~~~~\n\n")
+	buf.WriteString("\n" + long + "\n\n")
+
+	if cmd.Runnable() {
+		buf.WriteString(fmt.Sprintf("::\n\n  %s\n\n", cmd.UseLine()))
+	}
+
+	if len(cmd.Example) > 0 {
+		buf.WriteString("Examples\n")
+		buf.WriteString("~~~~~~~~\n\n")
+		buf.WriteString(fmt.Sprintf("::\n\n%s\n\n", indentString(cmd.Example, "  ")))
+	}
+
+	if err := printOptionsReST(buf, cmd, name); err != nil {
+		return err
+	}
+	if hasSeeAlso(cmd) {
+		buf.WriteString("SEE ALSO\n")
+		buf.WriteString("~~~~~~~~\n\n")
+		if cmd.HasParent() {
+			parent := cmd.Parent()
+			pname := parent.CommandPath()
+			ref = strings.Replace(pname, " ", "_", -1)
+			buf.WriteString(fmt.Sprintf("* %s \t - %s\n", linkHandler(pname, ref), parent.Short))
+			cmd.VisitParents(func(c *cobra.Command) {
+				if c.DisableAutoGenTag {
+					cmd.DisableAutoGenTag = c.DisableAutoGenTag
+				}
+			})
+		}
+
+		children := cmd.Commands()
+		sort.Sort(byName(children))
+
+		for _, child := range children {
+			if !child.IsAvailableCommand() || child.IsAdditionalHelpTopicCommand() {
+				continue
+			}
+			cname := name + " " + child.Name()
+			ref = strings.Replace(cname, " ", "_", -1)
+			buf.WriteString(fmt.Sprintf("* %s \t - %s\n", linkHandler(cname, ref), child.Short))
+		}
+		buf.WriteString("\n")
+	}
+	if !cmd.DisableAutoGenTag {
+		buf.WriteString("*Auto generated by spf13/cobra on " + time.Now().Format("2-Jan-2006") + "*\n")
+	}
+	_, err := buf.WriteTo(w)
+	return err
+}
+
+// GenReSTTree will generate a ReST page for this command and all
+// descendants in the directory given.
+// This function may not work correctly if your command names have `-` in them.
+// If you have `cmd` with two subcmds, `sub` and `sub-third`,
+// and `sub` has a subcommand called `third`, it is undefined which
+// help output will be in the file `cmd-sub-third.1`.
+func GenReSTTree(cmd *cobra.Command, dir string) error {
+	emptyStr := func(s string) string { return "" }
+	return GenReSTTreeCustom(cmd, dir, emptyStr, defaultLinkHandler)
+}
+
+// GenReSTTreeCustom is the the same as GenReSTTree, but
+// with custom filePrepender and linkHandler.
+func GenReSTTreeCustom(cmd *cobra.Command, dir string, filePrepender func(string) string, linkHandler func(string, string) string) error {
+	for _, c := range cmd.Commands() {
+		if !c.IsAvailableCommand() || c.IsAdditionalHelpTopicCommand() {
+			continue
+		}
+		if err := GenReSTTreeCustom(c, dir, filePrepender, linkHandler); err != nil {
+			return err
+		}
+	}
+
+	basename := strings.Replace(cmd.CommandPath(), " ", "_", -1) + ".rst"
+	filename := filepath.Join(dir, basename)
+	f, err := os.Create(filename)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	if _, err := io.WriteString(f, filePrepender(filename)); err != nil {
+		return err
+	}
+	if err := GenReSTCustom(cmd, f, linkHandler); err != nil {
+		return err
+	}
+	return nil
+}
+
+// adapted from: https://github.com/kr/text/blob/main/indent.go
+func indentString(s, p string) string {
+	var res []byte
+	b := []byte(s)
+	prefix := []byte(p)
+	bol := true
+	for _, c := range b {
+		if bol && c != '\n' {
+			res = append(res, prefix...)
+		}
+		res = append(res, c)
+		bol = c == '\n'
+	}
+	return string(res)
+}
diff --git a/vendor/github.com/spf13/cobra/doc/rest_docs.md b/vendor/github.com/spf13/cobra/doc/rest_docs.md
new file mode 100644
index 00000000..6098430e
--- /dev/null
+++ b/vendor/github.com/spf13/cobra/doc/rest_docs.md
@@ -0,0 +1,114 @@
+# Generating ReStructured Text Docs For Your Own cobra.Command
+
+Generating ReST pages from a cobra command is incredibly easy. An example is as follows:
+
+```go
+package main
+
+import (
+	"log"
+
+	"github.com/spf13/cobra"
+	"github.com/spf13/cobra/doc"
+)
+
+func main() {
+	cmd := &cobra.Command{
+		Use:   "test",
+		Short: "my test program",
+	}
+	err := doc.GenReSTTree(cmd, "/tmp")
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+```
+
+That will get you a ReST document `/tmp/test.rst`
+
+## Generate ReST docs for the entire command tree
+
+This program can actually generate docs for the kubectl command in the kubernetes project
+
+```go
+package main
+
+import (
+	"log"
+	"io/ioutil"
+	"os"
+
+	"k8s.io/kubernetes/pkg/kubectl/cmd"
+	cmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"
+
+	"github.com/spf13/cobra/doc"
+)
+
+func main() {
+	kubectl := cmd.NewKubectlCommand(cmdutil.NewFactory(nil), os.Stdin, ioutil.Discard, ioutil.Discard)
+	err := doc.GenReSTTree(kubectl, "./")
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+```
+
+This will generate a whole series of files, one for each command in the tree, in the directory specified (in this case "./")
+
+## Generate ReST docs for a single command
+
+You may wish to have more control over the output, or only generate for a single command, instead of the entire command tree. If this is the case you may prefer to `GenReST` instead of `GenReSTTree`
+
+```go
+	out := new(bytes.Buffer)
+	err := doc.GenReST(cmd, out)
+	if err != nil {
+		log.Fatal(err)
+	}
+```
+
+This will write the ReST doc for ONLY "cmd" into the out, buffer.
+
+## Customize the output
+
+Both `GenReST` and `GenReSTTree` have alternate versions with callbacks to get some control of the output:
+
+```go
+func GenReSTTreeCustom(cmd *Command, dir string, filePrepender func(string) string, linkHandler func(string, string) string) error {
+	//...
+}
+```
+
+```go
+func GenReSTCustom(cmd *Command, out *bytes.Buffer, linkHandler func(string, string) string) error {
+	//...
+}
+```
+
+The `filePrepender` will prepend the return value given the full filepath to the rendered ReST file. A common use case is to add front matter to use the generated documentation with [Hugo](http://gohugo.io/):
+
+```go
+const fmTemplate = `---
+date: %s
+title: "%s"
+slug: %s
+url: %s
+---
+`
+filePrepender := func(filename string) string {
+	now := time.Now().Format(time.RFC3339)
+	name := filepath.Base(filename)
+	base := strings.TrimSuffix(name, path.Ext(name))
+	url := "/commands/" + strings.ToLower(base) + "/"
+	return fmt.Sprintf(fmTemplate, now, strings.Replace(base, "_", " ", -1), base, url)
+}
+```
+
+The `linkHandler` can be used to customize the rendered links to the commands, given a command name and reference. This is useful while converting rst to html or while generating documentation with tools like Sphinx where `:ref:` is used:
+
+```go
+// Sphinx cross-referencing format
+linkHandler := func(name, ref string) string {
+    return fmt.Sprintf(":ref:`%s <%s>`", name, ref)
+}
+```
diff --git a/vendor/github.com/spf13/cobra/doc/util.go b/vendor/github.com/spf13/cobra/doc/util.go
new file mode 100644
index 00000000..8d3dbece
--- /dev/null
+++ b/vendor/github.com/spf13/cobra/doc/util.go
@@ -0,0 +1,51 @@
+// Copyright 2015 Red Hat Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package doc
+
+import (
+	"strings"
+
+	"github.com/spf13/cobra"
+)
+
+// Test to see if we have a reason to print See Also information in docs
+// Basically this is a test for a parent commend or a subcommand which is
+// both not deprecated and not the autogenerated help command.
+func hasSeeAlso(cmd *cobra.Command) bool {
+	if cmd.HasParent() {
+		return true
+	}
+	for _, c := range cmd.Commands() {
+		if !c.IsAvailableCommand() || c.IsAdditionalHelpTopicCommand() {
+			continue
+		}
+		return true
+	}
+	return false
+}
+
+// Temporary workaround for yaml lib generating incorrect yaml with long strings
+// that do not contain \n.
+func forceMultiLine(s string) string {
+	if len(s) > 60 && !strings.Contains(s, "\n") {
+		s = s + "\n"
+	}
+	return s
+}
+
+type byName []*cobra.Command
+
+func (s byName) Len() int           { return len(s) }
+func (s byName) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
+func (s byName) Less(i, j int) bool { return s[i].Name() < s[j].Name() }
diff --git a/vendor/github.com/spf13/cobra/doc/yaml_docs.go b/vendor/github.com/spf13/cobra/doc/yaml_docs.go
new file mode 100644
index 00000000..ea00af07
--- /dev/null
+++ b/vendor/github.com/spf13/cobra/doc/yaml_docs.go
@@ -0,0 +1,169 @@
+// Copyright 2016 French Ben. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package doc
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+
+	"github.com/spf13/cobra"
+	"github.com/spf13/pflag"
+	"gopkg.in/yaml.v2"
+)
+
+type cmdOption struct {
+	Name         string
+	Shorthand    string `yaml:",omitempty"`
+	DefaultValue string `yaml:"default_value,omitempty"`
+	Usage        string `yaml:",omitempty"`
+}
+
+type cmdDoc struct {
+	Name             string
+	Synopsis         string      `yaml:",omitempty"`
+	Description      string      `yaml:",omitempty"`
+	Options          []cmdOption `yaml:",omitempty"`
+	InheritedOptions []cmdOption `yaml:"inherited_options,omitempty"`
+	Example          string      `yaml:",omitempty"`
+	SeeAlso          []string    `yaml:"see_also,omitempty"`
+}
+
+// GenYamlTree creates yaml structured ref files for this command and all descendants
+// in the directory given. This function may not work
+// correctly if your command names have `-` in them. If you have `cmd` with two
+// subcmds, `sub` and `sub-third`, and `sub` has a subcommand called `third`
+// it is undefined which help output will be in the file `cmd-sub-third.1`.
+func GenYamlTree(cmd *cobra.Command, dir string) error {
+	identity := func(s string) string { return s }
+	emptyStr := func(s string) string { return "" }
+	return GenYamlTreeCustom(cmd, dir, emptyStr, identity)
+}
+
+// GenYamlTreeCustom creates yaml structured ref files.
+func GenYamlTreeCustom(cmd *cobra.Command, dir string, filePrepender, linkHandler func(string) string) error {
+	for _, c := range cmd.Commands() {
+		if !c.IsAvailableCommand() || c.IsAdditionalHelpTopicCommand() {
+			continue
+		}
+		if err := GenYamlTreeCustom(c, dir, filePrepender, linkHandler); err != nil {
+			return err
+		}
+	}
+
+	basename := strings.Replace(cmd.CommandPath(), " ", "_", -1) + ".yaml"
+	filename := filepath.Join(dir, basename)
+	f, err := os.Create(filename)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	if _, err := io.WriteString(f, filePrepender(filename)); err != nil {
+		return err
+	}
+	if err := GenYamlCustom(cmd, f, linkHandler); err != nil {
+		return err
+	}
+	return nil
+}
+
+// GenYaml creates yaml output.
+func GenYaml(cmd *cobra.Command, w io.Writer) error {
+	return GenYamlCustom(cmd, w, func(s string) string { return s })
+}
+
+// GenYamlCustom creates custom yaml output.
+func GenYamlCustom(cmd *cobra.Command, w io.Writer, linkHandler func(string) string) error {
+	cmd.InitDefaultHelpCmd()
+	cmd.InitDefaultHelpFlag()
+
+	yamlDoc := cmdDoc{}
+	yamlDoc.Name = cmd.CommandPath()
+
+	yamlDoc.Synopsis = forceMultiLine(cmd.Short)
+	yamlDoc.Description = forceMultiLine(cmd.Long)
+
+	if len(cmd.Example) > 0 {
+		yamlDoc.Example = cmd.Example
+	}
+
+	flags := cmd.NonInheritedFlags()
+	if flags.HasFlags() {
+		yamlDoc.Options = genFlagResult(flags)
+	}
+	flags = cmd.InheritedFlags()
+	if flags.HasFlags() {
+		yamlDoc.InheritedOptions = genFlagResult(flags)
+	}
+
+	if hasSeeAlso(cmd) {
+		result := []string{}
+		if cmd.HasParent() {
+			parent := cmd.Parent()
+			result = append(result, parent.CommandPath()+" - "+parent.Short)
+		}
+		children := cmd.Commands()
+		sort.Sort(byName(children))
+		for _, child := range children {
+			if !child.IsAvailableCommand() || child.IsAdditionalHelpTopicCommand() {
+				continue
+			}
+			result = append(result, child.Name()+" - "+child.Short)
+		}
+		yamlDoc.SeeAlso = result
+	}
+
+	final, err := yaml.Marshal(&yamlDoc)
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+
+	if _, err := w.Write(final); err != nil {
+		return err
+	}
+	return nil
+}
+
+func genFlagResult(flags *pflag.FlagSet) []cmdOption {
+	var result []cmdOption
+
+	flags.VisitAll(func(flag *pflag.Flag) {
+		// Todo, when we mark a shorthand is deprecated, but specify an empty message.
+		// The flag.ShorthandDeprecated is empty as the shorthand is deprecated.
+		// Using len(flag.ShorthandDeprecated) > 0 can't handle this, others are ok.
+		if !(len(flag.ShorthandDeprecated) > 0) && len(flag.Shorthand) > 0 {
+			opt := cmdOption{
+				flag.Name,
+				flag.Shorthand,
+				flag.DefValue,
+				forceMultiLine(flag.Usage),
+			}
+			result = append(result, opt)
+		} else {
+			opt := cmdOption{
+				Name:         flag.Name,
+				DefaultValue: forceMultiLine(flag.DefValue),
+				Usage:        forceMultiLine(flag.Usage),
+			}
+			result = append(result, opt)
+		}
+	})
+
+	return result
+}
diff --git a/vendor/github.com/spf13/cobra/doc/yaml_docs.md b/vendor/github.com/spf13/cobra/doc/yaml_docs.md
new file mode 100644
index 00000000..1a9b7c6a
--- /dev/null
+++ b/vendor/github.com/spf13/cobra/doc/yaml_docs.md
@@ -0,0 +1,112 @@
+# Generating Yaml Docs For Your Own cobra.Command
+
+Generating yaml files from a cobra command is incredibly easy. An example is as follows:
+
+```go
+package main
+
+import (
+	"log"
+
+	"github.com/spf13/cobra"
+	"github.com/spf13/cobra/doc"
+)
+
+func main() {
+	cmd := &cobra.Command{
+		Use:   "test",
+		Short: "my test program",
+	}
+	err := doc.GenYamlTree(cmd, "/tmp")
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+```
+
+That will get you a Yaml document `/tmp/test.yaml`
+
+## Generate yaml docs for the entire command tree
+
+This program can actually generate docs for the kubectl command in the kubernetes project
+
+```go
+package main
+
+import (
+	"io/ioutil"
+	"log"
+	"os"
+
+	"k8s.io/kubernetes/pkg/kubectl/cmd"
+	cmdutil "k8s.io/kubernetes/pkg/kubectl/cmd/util"
+
+	"github.com/spf13/cobra/doc"
+)
+
+func main() {
+	kubectl := cmd.NewKubectlCommand(cmdutil.NewFactory(nil), os.Stdin, ioutil.Discard, ioutil.Discard)
+	err := doc.GenYamlTree(kubectl, "./")
+	if err != nil {
+		log.Fatal(err)
+	}
+}
+```
+
+This will generate a whole series of files, one for each command in the tree, in the directory specified (in this case "./")
+
+## Generate yaml docs for a single command
+
+You may wish to have more control over the output, or only generate for a single command, instead of the entire command tree. If this is the case you may prefer to `GenYaml` instead of `GenYamlTree`
+
+```go
+	out := new(bytes.Buffer)
+	doc.GenYaml(cmd, out)
+```
+
+This will write the yaml doc for ONLY "cmd" into the out, buffer.
+
+## Customize the output
+
+Both `GenYaml` and `GenYamlTree` have alternate versions with callbacks to get some control of the output:
+
+```go
+func GenYamlTreeCustom(cmd *Command, dir string, filePrepender, linkHandler func(string) string) error {
+	//...
+}
+```
+
+```go
+func GenYamlCustom(cmd *Command, out *bytes.Buffer, linkHandler func(string) string) error {
+	//...
+}
+```
+
+The `filePrepender` will prepend the return value given the full filepath to the rendered Yaml file. A common use case is to add front matter to use the generated documentation with [Hugo](http://gohugo.io/):
+
+```go
+const fmTemplate = `---
+date: %s
+title: "%s"
+slug: %s
+url: %s
+---
+`
+
+filePrepender := func(filename string) string {
+	now := time.Now().Format(time.RFC3339)
+	name := filepath.Base(filename)
+	base := strings.TrimSuffix(name, path.Ext(name))
+	url := "/commands/" + strings.ToLower(base) + "/"
+	return fmt.Sprintf(fmTemplate, now, strings.Replace(base, "_", " ", -1), base, url)
+}
+```
+
+The `linkHandler` can be used to customize the rendered internal links to the commands, given a filename:
+
+```go
+linkHandler := func(name string) string {
+	base := strings.TrimSuffix(name, path.Ext(name))
+	return "/commands/" + strings.ToLower(base) + "/"
+}
+```