code: function(e){
            var status = $.status();
            if(status=='success'||status=='error') {
              $.callback(status, $.message());
              $.resumableObj.uploadNextChunk();
            } else {
              $.callback('retry', $.message());
              $.abort();
              $.retries++;
              var retryInterval = $.getOpt('chunkRetryInterval');
              if(retryInterval !== undefined) {
                $.pendingRetry = true;
                setTimeout($.send, retryInterval);
              } else {
                $.send();
              }
            }
          }
docs: Done (either done, failed or retry)