Factor out META

To make this service more generic and user friendly we'll begin
factoring out specific references to "META" and "Qualcomm". This will
eventually turn the service into a vanilla git poller and (perhaps)
allow us to ditch the service entirely in favor of something like
Buildbot (https://buildbot.net/).

Change-Id: Idc05595728a14c5858fbc4e2cefdbeb03928f867