UPBGE: Fix deletion of mathutils types in blenderplayer python.

The blenderplayer was not calling explicit initialization of mathutils and other
modules and let the user calls the initialization when importing them.
But some of the types defined on these modules can be returned by a python
function without requering to import the module, for example KX_GameObject.worldPosition
return a mathutils.Vector and some scripts don't import mathutils.

To solve this issue the initialization of the modules are explicitly called into
initPlayerPython by looping over bge_internal_modules and calling
PyImport_ImportModuleLevel.

It fix a major issue in blenderplayer scripts.

source/gameengine/Ketsji/KX_PythonInit.cpp

@@ -2067,13 +2067,12 @@ void initPlayerPython(int argc, char **argv)
 
 	bpy_import_init(PyEval_GetBuiltins());
 
-#ifdef WITH_AUDASPACE
-	/* accessing a SoundActuator's sound results in a crash if aud is not initialized... */
-	{
-		PyObject *mod = PyImport_ImportModuleLevel("aud", nullptr, nullptr, nullptr, 0);
+	/* The modules are imported to call their init functions to ensure the types they own are ready
+	 * as they are used outside of the modules. */
+	for (unsigned short i = 0; bge_internal_modules[i].name; ++i) {
+		PyObject *mod = PyImport_ImportModuleLevel(bge_internal_modules[i].name, nullptr, nullptr, nullptr, 0);
 		Py_DECREF(mod);
 	}
-#endif
 }
 
 void exitPlayerPython()