Inherit tp_new and tp_is_gc.

Bugfix candidate.
diff --git a/Objects/typeobject.c b/Objects/typeobject.c
index f0e8c83..849840c 100644
--- a/Objects/typeobject.c
+++ b/Objects/typeobject.c
@@ -2024,6 +2024,8 @@
 		COPYSLOT(tp_init);
 		COPYSLOT(tp_alloc);
 		COPYSLOT(tp_free);
+		COPYSLOT(tp_new);
+		COPYSLOT(tp_is_gc);
 	}
 }