The current method for actually triggering jobs in buildbot from taskotron-trigger is a bit hacky at best. It logs into buildbot using a defined user and forces builds with correct parameters.

While it has been working fine, it has a couple of specific issues that need to be addressed:
* prevents FAS integration for buildbot
* isn't terribly secure if someone got ahold of the username/password
* won't work with a multimaster configuration

While looking into buildbot's multimaster feature, I found a better way to trigger builds using change sources, which is a less dirty hack. The advantages to this approach are:
* gets triggering off of the public html interface so we can restrict it to just the host on which trigger is actually running
* doesn't rely on the public html auth and would allow for FedOAuth integration (read: FAS accounts instead of local accounts)
* is more future-proof if we move to a multi-master configuration