tree e5cb00430d16de1efb59ab39652faf8dd0dff93c
parent e46d6ad2b7a1033385eb80fc641be930c985a7ca
author Sean McGinnis <sean.mcginnis@huawei.com> 1518702310 -0600
committer Sean McGinnis <sean.mcginnis@huawei.com> 1518715275 -0600

Centralize setting default branch for stable branching

One of the steps when we create a new stable branch is to
branch devstack, then update the default branch for most
repos to use the new stable branch for each repo.

This requires making multiple updates throughout stackrc,
and to further complicate things, there are some repo
branch variables for branchless repos that should not be
updated along with the others.

This can be error prone if not fully aware of these
exceptions. To simplify this process a little, this
patch adds two common variables - one that can be set to
the new stable branch name for all of the repos that
should be branched, and one that can be used for all of
the branchless repos to make it explicit that those
values should be left alone. The cycle-trailing repos
have until two weeks after final release to branch, so
also adding another variable for those to make it easy
to update them at a later time, separately from the
other repos.

Change-Id: I82aa19e739eeda3721bac1cb5153ad0bf2d1125a