Resolves issue #23.

Adds audio output display and management options supporting mono and 
stereo output options.

Provides audio output supporting prioritization by talkgroup and/or 
channel selection.

Supports muting all channels, or muting individual channels and
individual audio gain/volume controls.

src/settings/SettingsManager.java

@@ -434,7 +434,7 @@ public class SettingsManager
 		return null;
 	}
 	
-	private ImageIcon getScaledIcon( ImageIcon original, int height )
+	public static ImageIcon getScaledIcon( ImageIcon original, int height )
 	{
 		double scale = (double)original.getIconHeight() / (double)height;