docs: function (key, config) {
    var props = key.split(',');
    this._cfg = {
      key:        key,
      properties: props,
      name:       config.name || camelize(props.join('_')),
      toGoogle:   config.toGoogle || null,
      fromGoogle: config.fromGoogle || null,
      read:       config.read || null,
      write:      config.write || null,
      event:      config.event || null,
      cast:       config.cast || null,
      readOnly:   config.readOnly || false,
      optionOnly: config.optionOnly || false
    };
  }