Ability to release from a branch

[dave-gantenbein]

We need this in case we need to quickly patch a release that's currently in production, but we don't want to release changes that have already made it to master. This actually happened a couple of weeks ago and we ended up having to revert a bunch of changes from master and then re-apply them once the patched release had been made. I think ideally we'd define a branch pattern for hotfixes that would mark the branch as releasable (maybe something like .-patch-[0-9] ) thus triggering all the same protections as the master branch and causing a release to be made on PR merge