sendFunc = function () {
                req.date = new Date();
                if (self._conn.options.customHeaders){
                    var headers = self._conn.options.customHeaders;
                    for (var header in headers) {
                        if (headers.hasOwnProperty(header)) {
                            req.xhr.setRequestHeader(header, headers[header]);
                        }
                    }
                }
                req.xhr.send(req.data);
            }
PrivateFunction: _processRequest
 _Private_ function to process a request in the queue.

 This function takes requests off the queue and sends them and
 restarts dead requests.

 Parameters:
   (Integer) i - The index of the request in the queue.