code: @SuppressWarnings("unchecked")
      public static NamingService<VM> getVMNames(Model mo) {
          return (NamingService<VM>) mo.getView(ID + VM.TYPE);
      }
docs: Get the naming service for the VMs associated to a model.
  
  @param mo the model to look at
  @return the view if attached. {@code null} otherwise