Renamed package "dimitri.suls.allshare.media" to
"dimitri.suls.allshare.avplayer".
Renamed media-events to AVPlayer-events.
Added slider to adjust AV-player volume.
Added switch to mute/unmute AV-player.
Increased size of lists from 100dp to 120dp, because the footer of
selectedDevice has been removed a while ago.
Added empty listeners for the AVPlayer, and set them in the
DeviceManager.