Rename git-core rpm to just git and rename the meta-pacakge to git-all.

Rename git-core rpm to just git and rename the meta-pacakge to git-all.

This fixes my favorite annoyance with the git rpm packaging: don't pull
in tla when I say yum install git!  You wouldn't expect yum install gcc
to pull in gcc-gfortran, right?

With this change, and blanket 'yum update' will automatically pull in the
new 'git' package and push out the old 'git-core', and if the old 'git'
package was installed 'git-all' will be pulled in instead.  A couple of
things do break though: 'yum update git-core', because yum behaves
differently when given a specific package name - it doesn't follow obsoletes.

Instead, 'yum install git' will pull in the new git rpm, which will then
push out the old 'git-core'.  Similarly, to get the newest version of
the meta package, 'yum install git-all' will install git-all, which then
pushes out the old 'git' meta package.

Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>