Unified behaviour of generated and non-generated factories

First commit is just to unify behaviour with comments in return annotations.

Second comit fixes the fact that https://github.com/nette/nette/commit/40e7b8f40054d5db2d4a08b23bff6361fec1dd1c only works for generated factories but not for non-generated factories. Example (throws exception class App\Application\IRouter not found):

```php
namespace App\Application;

use Nette\Application\IRouter;
use Nette\Application\Routers\Route;
use Nette\Application\Routers\RouteList;
use Nette\Object;

/**
 * Router factory.
 */
final class RouterFactory extends Object
{

	/**
	 * @return IRouter
	 */
	public function create()
	{
		$router = new RouteList('Front');
		$router[] = new Route('<presenter>/<action>[/<id>]', 'Homepage:default');

		return $router;
	}

}
```