Support video-only streams if there is no audio in the inbound stream. (#401)

Closes #400

core/streamState.go

@@ -43,6 +43,7 @@ func setStreamAsConnected() {
 
 	go func() {
 		_transcoder = ffmpeg.NewTranscoder()
+		_transcoder.SetVideoOnly(_broadcaster.StreamDetails.VideoOnly)
 		_transcoder.TranscoderCompleted = func(error) {
 			SetStreamAsDisconnected()
 		}