Game Events

-game begins with a title screen and ends with a game over notice
-pressing one of the jump buttons starts a new game.
-new folder named Managers and put a new C# script named
GameEventManager in it. We make GameEventManager a static class that
defines a GameEvent delegate type inside it
-new gameEvent type to add two events to our manager, GameStart and
GameEnd.
-need to include a way to trigger these events, add two methods for
this.