Renamed GameEngine and GameState. Starting to add in classes for renderer and camera object.
Moved out GLFWGraphics into it's own concrete header.
Cleaned up some more header includes.
Renamed GameState.cpp. Forgot to check in.
Made a macro FACTORY_HOLDER that creates the appropriate constructor and member variable for classes that want to use this pattern.
Added Concrete implementations for Renderer, Resource manager.
Removed renderer init from demo. It is now being controlled by GameEngine.
Added resource manager load method. resource manager will be an instance resolved object that gets created in main when we do type registration.