title: TimerManager with random recurTime
body: <p>I want a random expiration time on <strong>EACH</strong> iteration.
  This example will only randomize an expiration time between 5~15 seconds and use them forever.</p>
  
  <pre><code>var timer = qx.util.TimerManager.getInstance();
  timer.start(function(userData, timerId)
      {
          this.debug("timer tick");
      },
      (Math.floor(Math.random()*11)*1000) + 5000,
      this,
      null,
      0
  );
  </code></pre>
  
  <p>I also accept an pure JS solution if any.</p>
  
  <p><a href="http://demo.qooxdoo.org/current/apiviewer/#qx.util.TimerManager" rel="nofollow">http://demo.qooxdoo.org/current/apiviewer/#qx.util.TimerManager</a></p>