[PATCH] Teach "git-rev-parse" about date-based cut-offs

[PATCH] Teach "git-rev-parse" about date-based cut-offs

This adds the options "--since=date" and "--before=date" to git-rev-parse,
which knows how to translate them into seconds since the epoch for
git-rev-list.

With this, you can do

	git log --since="2 weeks ago"

or

	git log --until=yesterday

to show the commits that have happened in the last two weeks or are
older than 24 hours, respectively.

The flags "--after=" and "--before" are synonyms for --since and --until,
and you can combine them, so

	git log --after="Aug 5" --before="Aug 10"

is a valid (but strange) thing to do.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>