code: protected boolean deleteModel(MODEL_ID id, boolean permanent) throws Exception {
          if (permanent) {
              server.deletePermanent(modelType, id);
          } else {
              server.delete(modelType, id);
          }
          return permanent;
      }
docs: delete a model
  
  @param id        model id
  @param permanent a boolean.
  @return if true delete from physical device, if logical delete return false, response status 202
  @throws java.lang.Exception if any.