code: function(callback) {
              callback = callback || function() {};
              
              var that = this;
              var params = {
                  count: this._pagesize,
                  offset: this._offset
              };
              return this._endpoint(params, function(err, results) {
                  if (err) {
                      callback(err);
                  }
                  else {                    
                      var numResults = (results.rows ? results.rows.length : 0);
                      that._offset += numResults;
                      
                      callback(null, results, numResults > 0);
                  }
              });
          }
docs: Fetches the next page from the endpoint.