Scanning new library paths should also add artist playlists, otherwise
they won't show up until Ocarina is restarted.
Fixes#79: Artist playlists not updated when tracks are added
Signed-off-by: Anna Schumaker <Anna@NoWheyCreamery.com>
The pl_artist_init() function is used to allocate a playlist for each
artist already in the database, and pl_artist_deinit() is then used to
free up this memory during cleanup.
Signed-off-by: Anna Schumaker <Anna@OcarinaProject.net>