Artist in album not found due to case

[tonarec]

Context
If an artist exists but with a different case, the wrapper will try to create it instead of retrieving the actual artist.
Example:

• Artist name: FooBar (id: 12345)
• Artist name: FOOBAR (id: 67890)

Scenario

• Adding a track with add_track_to_database(path, title, artist), with artist='FooBar'
• The artist already exist with 'FOOBAR'
• After creation of the artist, the album can't be found because the combinaison of AlbumName+ArtistID didn't match
• The error is trigger when add_album() is used because the AlbumName already exists

Fix

• The add_album() method should not ignore the ArtistID
• Check for duplicated AlbumName first
• If duplicated, try to create a new album with the new artist instead (assuming there are not the same artists due to case)