function initializePlaylistActiveIndexes() {
    /*
    Iterate over all of the playlists defined by the user
      and add an active index.
    */
    for (var key in _config2.default.playlists) {
      _config2.default.playlists[key].active_index = null;
    }
  }
Initializes a scoped active index for each playlist.

@access private