group(prefix, callback) {
    this._groupData = {prefix};
    callback();
    this._groupData = null;
  }
Can be used to add prefix to all routes defined in the callback

Route.group('/users', () => {
  Route.on('/edit/{id}', UsersEditPage);
  Route.on('/delete/{id}', UsersDeletePage);
});

@param prefix
@param callback