Rename the "Clear List & Play" options to simply Play and Play
Shuffled, and change their behavior slightly. Previously they
would leave the current song playing, but now they will start
playing the first song of the new playlist immediately.
Shuffle options are now consistently hidden whenever a single
file is selected.
Fixes FS#13336 -- Play Shuffled is now always displayed where
applicable, regardless of playback state.
Change-Id: Idd454b4f9ab2c98cda3ce0389add747a3273fb42
70087fb9f3