Using app.configure in example code

In the example code we are using

```
app.configure(function() {
app.use(express.cookieParser('keyboard cat'));
app.use(express.session({ cookie: { maxAge: 60000 }}));
app.use(flash());
});
```

But app.configure is removed in Express 4.0.

Locate the example code shown in the issue and compare its configuration style with Express 4 guidance. Update the example so it no longer uses app.configure, then verify that the documented snippet reflects supported Express 4 usage.

Written by the indexing model from the issue text.