Tried to make audio streams stutter less on Unix.

Will have to investigate this a bit further someday.
Postpone until (if ever) Henri explains his decision to choke down
priority of new slplugin processes down to idle.

indra/newview/llviewermedia_streamingaudio.cpp

@@ -165,6 +165,7 @@ LLPluginClassMedia* LLStreamingAudio_MediaPlugins::initializeMedia(const std::st
 	if (media_source)
 	{
 		media_source->setLoop(false); // audio streams are not expected to loop
+		media_source->setPriority(LLPluginClassMedia::PRIORITY_HIGH); // don't stutter on me! -SG
 	}
 
 	return media_source;