message: ref: Use a named function for the middleware over an anonymous
  It's making the investigation of performance issues easier.
diff: @@ -532,7 +532,7 @@ extend(Raven.prototype, {
  requestHandler: function() {
  var self = this;
  - return function(req, res, next) {
  + return function ravenMiddleware(req, res, next) {
  self.context({req: req}, function() {
  domain.active.add(req);
  domain.active.add(res);
  