* in VideoMode setting of a feed, added "Use muxed video" option if use video, to use the muxed video stream
	* regardless it's set or not, if separate audio/video is not available, muxed video stream is the last resort
* force reset playback of current media when feed VideoMode, audio quality, or video quality changes
* in PlayerUI, resolution is shown when playing video
* likely fixed clients mal-functioning after toggling "Use external apps"
