unauthorized(msg, details) {
    this.status(401);
    this.render(API.error(msg || 'Unauthorized', details));
    return true;
  }
Using API formatting, send an http.ServerResponse indicating there was an Unauthorized request (401)
@param {string} msg Error message to send
@param {Object} details Any additional details for the error (must be serializable)
@return {boolean}