[racket-dev] Release for v6.0 has begun

The release process for v6.0 has begun: the `release' branch was
created for any work that is left and is now bumped to v5.91.  You
can go on using the `master' branch as usual, it is now bumped to
v6.0.0.1 (to avoid having two different trees with the same version).

If you have any bug-fixes and changes that need to go in the release
then make sure to specify that in the commit message or mail me the
commit SHA1s.  You can `git checkout release' to try it out directly if
needed -- but do not try to push commits on it (the server will forbid
it).

Please make sure that code that you're responsible for is as stable
as possible, and let me know if there is any new work that should
not be included in this release.

       >> NOW IS THE TIME TO FIX BUGS THAT YOU KNOW ABOUT <<<

The time between the `release' branch creation and the actual
release is for fixing new errors that prevent proper functioning of
major components and that show up during the preparation for a
release.  You can also finalize piece of work that is not yet
complete, but please avoid merging new features.

Note that nightly builds will go on as usual (starting from
v6.0.0.1 and going up as usual), and pre-release builds will be
available shortly at

   http://pre.racket-lang.org/release/

Please tell me if you think that this release is significant enough
that it should be announced on the users list for wider testing.