Feature request: controller test template

> What?
> http://symfony.com/doc/current/book/testing.html#your-first-functional-test
> 
> Where?
> 
> ```
> Rightclick on editor with controller => Generate => Functional Test (with Symfony icon)
> Rightclick on folder => New => PHPUnit => Controller Functional Test (with Symfony icon)
> ```

origin:
https://github.com/Haehnchen/idea-php-symfony2-plugin-doc/issues/5
