UI: Use utvideo for lossless compression

After some more testing, utvideo not only gives better encoding
performance, but also better compression and better decoding
performance.  It's pretty much superior all around over huffyuv.

obs/window-basic-main-outputs.cpp

@@ -154,7 +154,7 @@ void SimpleOutput::LoadRecordingPreset_Lossless()
 
 	obs_data_t *settings = obs_data_create();
 	obs_data_set_string(settings, "format_name", "avi");
-	obs_data_set_string(settings, "video_encoder", "huffyuv");
+	obs_data_set_string(settings, "video_encoder", "utvideo");
 	obs_data_set_int(settings, "audio_bitrate", 512);
 	obs_data_set_string(settings, "audio_encoder", "ac3");