Access to $loop using new App ().
Hello, I'm using Ratchet in my Term paper. 
By analyzing the code I saw that I can access the '$loop' 
even using the "new App (...)" for initialization, but on trying this is returning "null"

```php
...
    $app = new App("localhost");

    var_dump($app->flashServer->loop); // null
....
```
Even creating the external "$loop" and including as a parameter I get "null".

```php
...
   $loop = \React\EventLoop\Factory::create();
    $app = new App("localhost", 8080, $address = '127.0.0.1', $loop);

    var_dump($app->flashServer->loop); // null
...
```

Is it possible to access $ loop using "new App (...)"? I'm doing it wrong?
