Fixed incorrect indexing in GetData with Rectangle.
Fixed TargetElapsedTime to exactly match XNA.
Made a bunch of tests public to make it visible to the unit test runner GUI.
Fixed incorrect default inactive sleep time.
Throw the correct exception when the time is negative.
Fixed exception message being set as parameter name.
Fixed missing argument exception in Game.Content assignment.
RunOneFrame() should not throw afterGame is disposed.
Made a few more tests public for GUI runner.