code: function _handleResponse(o, c) {
          var status;
  
          try {
              if (o.c.status && o.c.status !== 0) {
                  status = o.c.status;
              }
              else {
                  status = 0;
              }
          }
          catch(e) {
              status = 0;
          }
  
          // IE reports HTTP 204 as HTTP 1223.
          if (status >= 200 && status < 300 || status === 1223) {
              _ioSuccess(o, c);
          }
          else {
              _ioFailure(o, c);
          }
      }
docs: @description Method that determines if a transaction response qualifies
  as success or failure, based on the response HTTP status code, and
  fires the appropriate success or failure events.
  
  @method _handleResponse
  @private
  @static
  @param {object} o - Transaction object generated by _create().
  @param {object} c - Configuration object passed to io().
  @return void