[Reviewer: Matt] Homestead as HSS development

Fixes issues: metaswitch/crest#164, metaswitch/crest#162, metaswitch/crest#47. In conjunction with Phil's change of moving monit to upstart metaswitch/crest#148 should also be fixed. Also, included are ENTs for improved craft/syslog logs. Plus, command line tools for provisioning subscribers in the absence of Ellis.
Is the logic here right?  If you construct a LevelLogObserver with level=logging.DEBUG, we'd end up reporting debug messages as `TWISTED_ERROR`s.  I think this comes back to my previous comment about needing comments to say exactly what these classes are for - it seems we've conflated logs output by Twisted with Twisted _errors_.