Added SoundEmitter::getDecodedLength and SoundEmitter::getDuration. The getDuration function will allow a timer to be registered to fire after the sound has been played. This is not a callback as requested but it does provide the functionality if required. I will be committing an example of it in the shooter demo shortly. [t:346]

<?fife type="object"?>
<object id="other:05" namespace="http://www.fifengine.de/xml/rio_de_hola" blocking="0" static="1">
	<image source="000.png" direction="0" />
</object>