title: back button shows previous page after logout in Symfony 2.1
body: <p>I have done project in <code>Symfony 2.1</code> in which session management works properly. i.e. after logout it shows login page.But while cliking on back button of browser it shows previous page which should not be shown as per requirements. If any action done on that page redirects to login screen again means no action is permitted after logout.
  I tried different solution shown by others like:</p>
  
  <p>In twig:</p>
  
  <pre><code>&lt;META Http-Equiv="Cache-Control" Content="no-cache, no-store, must-revalidate"&gt;
  &lt;META Http-Equiv="Pragma" Content="no-cache"&gt;
  &lt;META Http-Equiv="Expires" Content="0"&gt;
  </code></pre>
  
  <p>But didn't workout for me.Any other way specially in <code>Symfony</code> to prevent this.Any suggestions are helpful.</p>