Make "git gc" pack all refs by default

Make "git gc" pack all refs by default

I've taught myself to use "git gc" instead of doing the repack explicitly,
but it doesn't actually do what I think it should do.

We've had packed refs for a long time now, and I think it just makes sense
to pack normal branches too. So I end up having to do

	git pack-refs --all --prune

in order to get a nice git repo that doesn't have any unnecessary files.

So why not just do that in "git gc"? It's not as if there really is any
downside to packing branches, even if they end up changing later. Quite
often they don't, and even if they do, so what?

Also, make the default for refs packing just be an unambiguous "do it",
rather than "do it by default only for non-bare repositories". If you want
that behaviour, you can always just add a

	[gc]
		packrefs = notbare

in your ~/.gitconfig file, but I don't actually see why bare would be any
different (except for the broken reason that http-fetching used to be
totally broken, and not doing it just meant that it didn't even get
fixed in a timely manner!).

So here's a trivial patch to make "git gc" do a better job. Hmm?

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