Jamchart track tagging
Use Feature jam_charts. Add a column is_jamchart to source_track. Add has_jamchart_source to show_source_information
Duration for songs/:song
Showing the duration of instances of a tracks for a song requires a new Feature (setlist_song_play_maps_to_track) indicating a strong one to many relationship between song and tracks. This will require a song_id column on source_tracks and setlist_song_id