- use builderid as a foreign key instead of using buildername for the table buildrequests
 - addbuilset take a list of buildersID
 - check signatures for the BaseScheduler?'s addBuildsetForXxx methods
Add @defer.inlineCallbacks to br_consumer_cb and buildRequestAdded
I think this is needed since a12242da69e76f34cc45523c5a928b19e676d3ff. Dustin, do you confirm ?