Tracks & Playlists - new entity

[geoff-maddock]

As an app user I would like to be able to add an manage playlists of music (and video) that can be related to events or entities. The playlists could then be optionally displayed on the event or entity page or in other components. The playlists will contain URLs and metadata about the files so that they can be referenced in players such as HTML5 audio or video tags.

[geoff-maddock]

- schema for setlists
  - setlist
    - id
    - slug
    - name
    - performer
    - set_type_id int nullable
    - started_at  datetime nullable
    - length *summary? 
    - primary_link
    - created_at
    - created_by
    - updated_at
    - updated_by

  - set_type
    - id
    - name
    - order
    - created_at
    - updated_at

- track
  - id
  - slug
  - artist
  - title
  - release
  - format
  - discogs_link
  - bandcamp_link
  - primary_link
  - position

- setlist_track
  - id
  - track_id
  - setlist_id
  - position

- event_setlist
  - setlist_id
  - event_id
  - created_at
  - updated_at

- entity_setlist
  - setlist_id
  - entity_id
  - created_at
  - updated_at

- setlist_tag
  - setlist_id
  - tag_id
  - created_at
  - updated_at

- event_track
  - track_id
  - event_id
  - created_at
  - updated_at

- entity_track
  - entity_id
  - event_id
  - created_at
  - updated_at

- track_tag
  - track_id
  - tag_id
  - created_at
  - updated_at