nomadic buildbot

[classabbyamp]

TODOs:

• [x] auth
• [ ] remove various TODOs in code
• [x] test
• [x] make a replacement for btimefiles - #202
• [x] fix the irc bot notifications
• [ ] split off containers
• [ ] database host volume (on new build controller host)

nomad_host_volumes:
  - name: buildbot_database
    path: /data/buildbot
    read_only: false

closes #133

[classabbyamp]

we may need to do some special nginx config for this if we're putting it behind the proxy: https://docs.buildbot.net/current/manual/configuration/www.html#reverse-proxy-config