Branching

[Chong Yidong]

As mentioned in an earlier email, we can now cut the CVS branch for
Emacs 23.  Any futher 23.0.xx pretest(s), and the 23.1 release, will
come from the branch.

As currently planned, we'll use the trunk for developing 23.2.  But if a
bugfix-only release proves necessary (e.g. if serious bugs come to light
after we release 23.1), we can change course and make 23.2 from the
branch while bumping the trunk release to 23.3, similar to the original
development plan for the Emacs 21 series.

Has anyone given thought to the branch tag?  If we follow previous
conventions, we'd name the branch EMACS_23_BASE, but this is somewhat
misleading.