added more functionality to player turn mechanism

FILES MODIFIED:
- PlayerBall.cs
- PlayerTurnController.cs
Added Main Menu scene

- The Main Menu scene is dirt simple and uses two new assets, a Zugi_Roll_Title and a musical piece (CC-attribution license) called Open Those Bright Eyes
- Updated Constants scripts, if you need to refer to a scene by name, you can use the constant!
- Also added various fixes involving the presentaiton (sky bit counter, power increase on collisions)