updated stable branch

I just updated the stable branch to match master, which in my testing has been reliable and stable. I also changed the following Jenkins jobs to use the stable branch: Backport, BuildFarm, BinaryRelease, SourceRelease.

Note that now any Jenkins job that runs tests and validates them using the tcwgweb.sh script, the build and test run may succeed, but if there are any regressions, the dot will be Red now instead of Green. This primarily effects the Backport and the Release jobs.

- rob -