Cleaning up YAML to remove unnecessary sound properties
Rover voice changed to male
Created rover sounds layered sound definition.
Attempting to abstract away stopping sounds with no instance ID

Conflicts:
	source/rover.js
Wind and gameplay play on start again.
Hacky way to stopSound using triggers by retaining sounds in the soundManager
No need to provide sound instanceID anymore. Will stop all sounds if only soundName is provided.

Conflicts:
	source/marsGameSound.js
	source/marsGameSound.vwf.yaml
Merge pull request #126 from virtual-world-framework/sound-events

Sound events