title: How to get the "query string" from a QUrl?
body: <p>I have a QUrl and I need to extract the path+file+params. Basically everything but the hostname - what would be requested via HTTP.</p>
  
  <p>I looked through the Qt 4.6 docs but I couldn't find anything that looked like it would do this.</p>
  
  <p>What method(s) would I call?</p>