Some more Xact helpers.
Fixed randomized volume for wave playback to be scaled by the track volume.
Replaced the various Volume get/set properties with more obvious methods.
We now use the XactSound volume.
Did a bunch of cleanup in Cue.
Switched clip to use SoundState.
Moved all event playback timing into XactClip.
Found new event type.
Implemented volume events.
Merge pull request #2977 from SickheadGames/xact5

XAct Improvements 5