Done - until refactoring

I still have a few errors in my ray tracer. If you closely look at the green sphere, it should be cut by the plane. Also, the order that I add items to my scene object list currently matters in my ray tracer. This is because I do way too much of the scene shading in the object hit function. In order to fix this, I really need to add more methods to my parent GeometricObject class, and stop implementing things in the derived classes. This is going to take a bit of refactoring, but once I get some sort of version control (SVN) setup I should be able to move forward.