Merge pull request #7 from triplem/genre

Genre
Add posibility to keep existing tags, add freedb_id to tags, adopt image type for flac files (use 3, meaning front cover)
Enable to use lowercase directory and filenames
Add translation for german umlauts
Add discogs_id to metadata
Merge pull request #8 from triplem/destdir

Add destination directory as an option
Increment version
Merge branch 'master' into next_version