add the X-Requested-With header to fix AngularJs's ajax request

lib/util/http.js

@@ -18,6 +18,7 @@ exports.setup = function(req, res, next) {
     corsOpts.supportsCredentials = false;
   }
   
+  corsOpts.requestHeaders = corser.simpleRequestHeaders.concat(["X-Requested-With"]);
   var handler = corser.create(corsOpts);
   
   handler(req, res, function () {
@@ -130,4 +131,4 @@ exports.redirect = function(res, url, statusCode) {
 var autoParse = {
   'application/x-www-form-urlencoded': parseBody,
   'application/json': parseBody
-};
+};