(MVert,MFace,etc) off into DNA_meshdata_types.h, to isolate areas
of source that actually edit mesh *data* vs. areas that just edit
mesh object information.
#ifdef __APPLE__
#include <OpenGL/gl.h>
#else
#include <GL/gl.h>
#endif
(also for <GL/glu.h>)
so that people don't have to create symlinks in
/System/Library/Frameworks/OpenGL.framework on Mac OS X
(Charles Wardlaw)