title: How to change request URI in ExtJS 4.1.0 Proxy or Reader
body: <p>As it is, ExtJS 4.1 with a Rest proxy and a Json reader asks for a URI like this (urlencoded, though):</p>
  
  <p><code>http://localhost:8000/api/v1/choice/?filter=[{"property":"question_id","value":2}]</code></p>
  
  <p>my server wants filter requests to look like:</p>
  
  <p><code>http://localhost:8000/api/v1/choice/?question_id=2</code></p>
  
  <p>I've looked at the <code>filterParam</code> config for the proxy, but it doesn't seem relevant. Is there a practical way to achieve the request URI that the server needs?</p>