changed: It's nicer to close the music db on failure
fixed: Music album info gets stuck on failure (fixes #14435)
fixed: Storing (local) album art was broken (partial fix for #14345)
fixed: SQL query was wrong
fixed: Adding albums to the music-db without MusicBrainz info was broken
fixed: Formatting (cosmetics)
fixed: artist was being added as genre to music album table
fixed: Locally found music album art was not stored in the db ((partially?) fixes #14345)