- started cleanup of model code.

* refactored FBoundingBox so that the game dependent members are global functions now.
* changed some methods of the model renderer to take a render style parameter instead of a full actor.

src/common/rendering/gl/gl_buffers.cpp

@@ -37,6 +37,7 @@
 #include "gl_buffers.h"
 #include "gl_renderstate.h"
 #include "v_video.h"
+#include "flatvertices.h"
 
 namespace OpenGLRenderer
 {