Display list removal and GL context 3.2

Pull request for removing display list build & use from aurora/model.cpp. Not all references are removed - this is a simple remove from use. Further work will remove old references and complete some cleanup for it.

There's also a request for an OpenGL 3.2 compatibility context creation from SDL2. I recommend using compat. until such time as all deprecated features are removed and a core profile can be used instead.