[musicdb] adds GetArtist() replacement for GetArtistInfo()
[musicdb] Adds HasArtistScrapedInfo/ClearArtistLastScrapeTime and drop old methods
[musicdb] adds UpdateArtist() as a replacement for SetArtistInfo()
REVIEW: Adds SetArtistLastScrapeTime
REVIEW: Utilize SetArtistLastScrapeTime
[musicdb] use triggers for database consistency instead of deletes
[musicdb] retrieve the song artist credits in GetSong
[musicdb] Music Scanner updates
[musicdb] fix: remove unneeded rollbacktransaction
[musicdb] scan optimization - skip the scan if we don't find any music in the dir
[musicdb] fix artist fanart in infoscanner
[musicdb] add artist contributions (artists can have different names on individual songs/albums)
this allows for artists that have different names on some albums and songs
e.g. think about Prince vs TAFKAP - some albums have credits as prince, some as symbol
[musicdb] drop use of GROUP_CONCAT in albumview and instead use album.strArtists
[musicdb] construct the artist string from the artistCredits
[musicdb] fix: no longer force people to the musicbrainz scraper for MBID tagged music