git-commit -v: have patch at the end.

git-commit -v: have patch at the end.

It was pointed out that otherwise more important summary
information prefixed with '#' would become prone to be missed.

Also instead of chopping at the first '^---$' line, stop at the
first 'diff --git a/' line.

Signed-off-by: Junio C Hamano <junkio@cox.net>