builtin "git prune"

builtin "git prune"

This actually removes the objects to be pruned, unless you specify "-n"
(at which point it will just tell you which files it would prune).

This doesn't do the pack-file pruning that the shell-script used to do,
but if somebody really wants to, they could add it easily enough. I wonder
how useful it is, though, considering that "git repack -a -d" is just a
lot more efficient and generates a better end result.

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