git-bundle: various fixups

git-bundle: various fixups

verify_bundle() returned with an error early only when all
prerequisite commits were missing.  It should error out much
earlier when some are missing.

When the rev-list is limited in ways other than revision range
(e.g. --max-count or --max-age), create_bundle() listed all
positive refs given from the command line as if they are
available, but resulting pack may not have some of them.  Add a
logic to make sure all of them are included, and error out
otherwise.

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