Initial functional checkin of the controller

Note: This does not yet handle artifacts, nor the logs from the builder-core, as we don't yet have those interfaces exposed
Ah, I see how you're using it.  It might make more sense to declare it outside the `for{}` loop.  Then below, instead of of waiting for `len(currentJobs)` (and doing the builds in batches), you can just select over `done` forever and kick off new builds as any existing build finishes