GlUtils updates

- Added a 'getWireframeCubeGeometry' method to GlUtils
- Fixed an out-of-order error in the wireframe cube vertex indices array
- Removed a couple of chunks of commented-out code that's not really suitable for the public repo
- Fixed a bug in the addQuad() code that would try to re-use the local normal field instead of the vector (0, 0, 1) transformed by the current mesh transform.
- Removed an unused matrix parameter in the Interaction onKey call
- Fixed a bug in drawColorCube which caused it to ignore the 'lit' parameter