[BROKEN] Upgraded user, song, queuedsong models to Sequelize.

Added migration to create new tables, but not to migrate data.
Code expects old models. DJ is broken at this stage.
Fixed down migration for non-implemented down migrations.
File unlink hook promise chain now calls done().
Migrations to migrate data to/from song, file, queuedsong tables.
Always log debug messages to file.
Added migration to drop/create old song, file, queued_song tables.
Removed node-orm and node-migrate from project.

Project is still very broken.
Queued songs load again.
newBackboneDBModel can now create+update instances.

Songs can be reordered now.
Song playback works again.
Condensed console logging timestamps.
Songs can now be removed from queue.
Merge branch 'model-upgrade'. All models now converted.

Uploading songs is broken.
Made minor improvements to logging configuration.