code: function loadModels(mongoose, modelPath) {
      if (mongoose === undefined) {
          throw new Error('expect a mongoose handle to be passed');
      }
      return getMongoHandle(mongoose).then((modelHandle) => {
          debuglog(`got a mongo handle for ${modelPath}`);
          return _loadModelsFull(modelHandle, modelPath);
      });
  }
docs: expects an open connection!
  @param mongoose
  @param modelPath