game engine python api

* removed macros that were not used much, some misleading.
* removed error string setting calls that overwrote the error set by PyArg_ParseTuple with a less useful one.
* use python macros Py_RETURN_NONE, Py_RETURN_TRUE, Py_RETURN_FALSE

source/gameengine/Ketsji/KX_PythonInit.cpp

@@ -355,8 +355,7 @@ static PyObject *pyPrintExt(PyObject *,PyObject *,PyObject *)
 	if(!count)
 		pprint("No extenstions are used in this build");
 
-	Py_INCREF(Py_None);
-	return Py_None;
+	Py_RETURN_NONE;
 }