After looking over the things we expect to land in 1.13, I realized that
none of them are really required for legacy users, so I've gone ahead
and created a separate branch for py24 legacy systems (i.e. RHEL5).
This branch is client and builder only. Everything else has been removed.
Work on this branch will be as-needed, and it will be outside of our
With that done, we can now target python 2.6+ on the master branch. This
will allow us to speed up our py3 compatibility effort, and should ease
some contributor pain.