* EAGLView.cs: * minor cleanup

* MusicCubePlayback.cs: General cleanup
- C#-ised variable names
- added using statements
- other code cleanup
* EAGLView.cs: fixed depth rendering issue - added a depth render
  buffer

* Info.plist: modified to have a project type consistent with the
  Objective-C example

* MusicCube.csproj: made iPad view consistent with Objective-C example