I don't like the use of `__invoke` here, it's a little too magical/confusing.  Also, this does not allow for `POST`, or multiple routes per controller, which we do need in other parts of this demo.  I don't see anything wrong with the previous method, but if we want to make this logic happen in the `OAuth2Demo\Client\Client` class, we should do the following instead:

```php
// in OAuth2Demo\Client\Client.php
$routing->get('/', array(new HomepageController(), 'homepage'))->bind('homepage');
//...
```

This defines all routes in one place, but in a way that is not magical