message: Safely handle AliMergeable objects which don't implement unpacking
diff: @@ -675,14 +675,6 @@ Int_t DoReceive(aliZMQmsg::iterator block, void* socket)
  delete container;
  break;
  }
  - AliMergeable* unpackable = dynamic_cast<AliMergeable*>(object);
  - if (unpackable) {
  - if (fVerbose) printf("unpacking custom AliMergeable container %p\n", unpackable);
  - GetObjects(unpackable, &fListOfObjects);
  - if (fVerbose) printf("deleting custom AliMergeable container %p\n", unpackable);
  - delete unpackable;
  - break;
  - }
  }
  if (TCollection* collection = dynamic_cast<TCollection*>(object)) {
  