support proposed/* branches

provide support for named proposed branches for selection logic

Change-Id: Ia27fc54f41404a113065258e950adb2851f1ece8
switch swift enables to specify services

in the gate we specify all the swift services directly, not the
old swift flag. We should mirror that back to grenade, as we now
really do depend on it.

Change-Id: Id0ddf92c0c2d02dd3fb86e408a84646e081944da
Merge "support proposed/* branches"
Merge "switch swift enables to specify services"