Removed duplicated constants from c module

bob/io/image/main.cpp

@@ -43,9 +43,6 @@ static PyObject* create_module (void) {
   if (!m) return 0;
   auto m_ = make_safe(m);
 
-  /* register some constants */
-  if (PyModule_AddStringConstant(m, "__version__", BOB_EXT_MODULE_VERSION) < 0) return 0;
-
   /* imports dependencies */
   if (import_bob_blitz() < 0) {
     PyErr_Print();