code: function (deviceIdentifier, channelIdentifier, data) {
        var path,
            rejectMsg;
        if (deviceIdentifier && channelIdentifier && data) {
          path = this.constructPath(constants.DEVICES, deviceIdentifier, constants.CHANNELS, channelIdentifier);
          return this.Core.PATCH(path, data);
        } else {
          rejectMsg = 'Bad Request: A device identifier, a feed identifier and a data object are required.';
          return this.rejectRequest(rejectMsg);
        }
      }
docs: Update a feed on a channel
  @param  {String|Integer} deviceIdentifier  A Robin device identifier
  @param  {String|Integer} channelIdentifier A Robin channel identifier
  @param  {Object}         data              A querystring object
  @return {Function}                         A promise