title: How to generate URL with Slug and query string in symfony2
body: <p>I would like to generate a path in controller with a pattern like this -</p>
  
  <pre><code>mysite.com/slug?param=123
  </code></pre>
  
  <p>At the Moment I am doing this -</p>
  
  <pre><code>return $this-&gt;redirect($this-&gt;generateUrl('my_slug',array('page_slug'=&gt;'my_slug')));
  </code></pre>
  
  <p>I would like to append a query param to this url. Is it possible at all?</p>