Update app.js

To fix problems arising due to the asynchronous nature of .listen(). Really it should be doing that console.log call inside a callback passed to listen. When the host is added, it tries to do a DNS lookup, which is async. So when that line tries to fetch the address, there isn't one yet because the DNS request is running, so it crashes.

app.js

@@ -427,7 +427,7 @@ app.post('/search.:format?', loadUser, function(req, res) {
 });
 
 if (!module.parent) {
-  app.listen(3000);
-  console.log('Express server listening on port %d, environment: %s', app.address().port, app.settings.env)
+  app.listen(3000, 'localhost', function(){
+  console.log('Express server listening on port %d, environment: %s', app.address().port, app.settings.env)});
   console.log('Using connect %s, Express %s, Jade %s', connect.version, express.version, jade.version);
 }