Genericize object extension to allow for multiple extension contexts (e.g. Props and ActorMarkers)

include/recomp_data.h

@@ -2,8 +2,8 @@
 #define __RECOMP_DATA_H__
 
 namespace recomputil {
-    void init_extended_actor_data();
-    void reset_actor_data();
+    void init_extended_object_data(size_t num_types);
+    void clear_all_object_data(size_t type_index);
 
     void register_data_api_exports();
 }