Add support for artist group request (experimental)
The purpose of this is mainly to support Hyperfine Remote for Android
Fix group-type-type
Fixes two issues with Hyperfine Remote for Android

1. H. Remote uses the playpause command to both play and pause,
but forked-daapd would only support play, not pause.
2. H. Remote sends speaker id's in decimal, not in hex like other
remotes. Fixed so forked-daapd will understand both.
Merge branch 'fix_groups' into hyperfine
Fix error in c897761ee330e3c62d041c837abbb6f9b3b19b7c
Changed the way it's detected if speaker id is hex or dec
Autoselecting local audio just messes up speaker selection.