Mark assigned LIVE Assist Playlist as Music Bed

[radiorob]

When assigning a playlist to show up as buttons on LA, be able to mark/tag one of those assigned PL as "Music Bed" When the player runs this scheduled PL, the button player will show the buttons and this marked column will behave different on player when pressed. These music beds when pressed will be combined with local audio microphone for DJ to talk over. Player needs compatiblity to understand server PL type