Add Repository.Log() method (fix #298)

- CommitIter is now an interface
- The old CommitIter implementation is now called StorerCommitIter
- CommitWalker and CommitWalkerPost are now iterators (CommitPreIterator and CommitPostIterator).
- Remove Commit.History() method. There are so many ways to iterate a commit history, depending of the use case. Now, instead of use the History() method, you must use CommitPreIterator or CommitPostIterator.
- Move commitSorterer to references.go because is the only place that it is used, and it must not be used into another place.
- Make References method private, it must only be used into blame logic.
- Added a TODO into references method, where the sortCommits is used to remove it in a near future.

1 files changed, 6 insertions, 4 deletions

diff --git a/plumbing/object/commit_walker_test.go b/plumbing/object/commit_walker_test.go
index aa54de0..7d04bce 100644
--- a/plumbing/object/commit_walker_test.go
+++ b/plumbing/object/commit_walker_test.go
@@ -8,11 +8,12 @@ type CommitWalkerSuite struct {
 
 var _ = Suite(&CommitWalkerSuite{})
 
-func (s *CommitWalkerSuite) TestWalkHistory(c *C) {
+func (s *CommitWalkerSuite) TestCommitPreIterator(c *C) {
 	commit := s.commit(c, s.Fixture.Head)
 
 	var commits []*Commit
-	WalkCommitHistory(commit, func(c *Commit) error {
+	wIter := NewCommitPreIterator(commit)
+	wIter.ForEach(func(c *Commit) error {
 		commits = append(commits, c)
 		return nil
 	})
@@ -34,11 +35,12 @@ func (s *CommitWalkerSuite) TestWalkHistory(c *C) {
 	}
 }
 
-func (s *CommitWalkerSuite) TestWalkHistoryPost(c *C) {
+func (s *CommitWalkerSuite) TestCommitPostIterator(c *C) {
 	commit := s.commit(c, s.Fixture.Head)
 
 	var commits []*Commit
-	WalkCommitHistoryPost(commit, func(c *Commit) error {
+	wIter := NewCommitPostIterator(commit)
+	wIter.ForEach(func(c *Commit) error {
 		commits = append(commits, c)
 		return nil
 	})