SessionManagerFactory can set SessionConfig Options

As it can set the validators, it could also set the session config, reducing the need to implement a class for this.

From doc:
http://framework.zend.com/manual/2.3/en/modules/zend.session.config.html#custom-configuration

So on our module.config.php we could made it easy:
```
    'session_manager' => array(
        'config' => array(
            'name' => 'myApp',
        ),
        'validators' => array(
            'Zend\Session\Validator\RemoteAddr',
            'Zend\Session\Validator\HttpUserAgent',
        ),
    ),
```