Clean up date handling,

as a first step to get rid of the frequent petty warnings in this area:
 - always store dates as strings, not as seconds since the Epoch
 - for input, try the three most common formats everywhere
 - for unrecognized format, just pass the date though verbatim
 - when there is no date at all, still use the current date
Originally triggered by a one-line patch from Tim van der Molen,
<tbvdm at xs4all dot nl>, which is included here.
Feedback and OK on manual parts from jmc@.
"please check this in" kristaps@

1 files changed, 2 insertions, 1 deletions

diff --git a/main.c b/main.c
index 8c0c8ae0..db8d57a0 100644
--- a/main.c
+++ b/main.c
@@ -128,7 +128,8 @@ static	const char * const	mandocerrs[MANDOCERR_MAX] = {
 	"no title in document",
 	"document title should be all caps",
 	"unknown manual section",
-	"cannot parse date argument",
+	"date missing, using today's date",
+	"cannot parse date, using it verbatim",
 	"prologue macros out of order",
 	"duplicate prologue macro",
 	"macro not allowed in prologue",