Added Q, made database.init use a promise.
Winston catches uncaught errors. Also logs to .json now.
song_sources.init now returns a promise.
Rooms are loaded with a promise.
Uploads are initialized with a promise.
Handlers init now uses promise. App.js uses promises now.

You could say this refactoring is off to a... promising start!
Logging and socket.io init use promises.
Moved config checker to utils/load_config.js.

Also removed unused imports form app.js.