Annotation: Routing name is just appending to generic route name

This pr fix issue #878 

I have noticed, that if i use the annotation to declare a custom route the "name" attribute is just appended to the generic route name. 


```php
/**
* @FOSRest\Get("/users/{user}", name="get_user", requirements={"user" = "\d+|me"})
*/
public function getUserAction(User $user) { /** */ }

```

Current result:
```
get_userget_user                   GET      ANY    ANY  /users/{user}.{_format}

```

New result:
```
get_user                           GET      ANY    ANY  /users/{user}.{_format}

```