code: function makeGetterAndSetter(name, key) {
          moment.fn[name] = moment.fn[name + 's'] = function (input) {
              var utc = this._isUTC ? 'UTC' : '';
              if (input != null) {
                  this._d['set' + utc + key](input);
                  moment.updateOffset(this);
                  return this;
              } else {
                  return this._d['get' + utc + key]();
              }
          };
      }
docs: helper for adding shortcuts