Camera basics

The rail track path splines aren't done yet, but in the meantime I hooked up a proper camera. Now I can properly move the view around, and the debug view is working properly with it too

I've used Tiled to make a larger world to test with but it's still very dull and empty - now I can properly move the camera I can justify adding some nicer decor, since I figure I will be looking at it a lot in the weeks to come