[#22488] Reloading scripts causes crash

F8 key enabled again, useful for script UI development.

- keying set freeing wasnt freeing from all scenes and the builtin list.
- PointerProperty() cant refer to a removed python srna type (fixed in rigify and netrender).
- Added a check for freeing a type used by a PointerProperty but its very slow, makes reloading take ~10sec. Only enabled this in debug mode for now.

Netrender register() function isnt re-registering the property, probably because the module is cached by python and not re-run.

source/blender/python/generic/mathutils.h

@@ -74,19 +74,6 @@ int EXPP_VectorsAreEqual(float *vecA, float *vecB, int size, int floatSteps);
 #define Py_NEW  1
 #define Py_WRAP 2
 
-
-/* Mathutils is used by the BGE and Blender so have to define 
- * some things here for luddite mac users of py2.3 */
-#ifndef Py_RETURN_NONE
-#define Py_RETURN_NONE  return Py_INCREF(Py_None), Py_None
-#endif
-#ifndef Py_RETURN_FALSE
-#define Py_RETURN_FALSE  return Py_INCREF(Py_False), Py_False
-#endif
-#ifndef Py_RETURN_TRUE
-#define Py_RETURN_TRUE  return Py_INCREF(Py_True), Py_True
-#endif
-
 typedef struct Mathutils_Callback Mathutils_Callback;
 
 typedef int (*BaseMathCheckFunc)(BaseMathObject *);							/* checks the user is still valid */