REL9_1_STABLE branch created

Please remember to double-patch anything that should go into 9.1.

For the record, the correct formula seems to be

$ git pull
Current branch master is up to date.
$ git push origin master:refs/heads/REL9_1_STABLE
Total 0 (delta 0), reused 0 (delta 0)
To ssh://git@gitmaster.postgresql.org/postgresql.git* [new branch]      master -> REL9_1_STABLE

after which you can check out the branch locally according to whatever
formula you're already using (a separate workdir in my case).
        regards, tom lane