title: jQuery waypoints plugin - remove class when out of view
body: <p>I'm using waypoints plugin</p>
  
  <pre><code>$('.thing').waypoint(function(direction) {
      jQuery(".block7").addClass("active");
  });
  </code></pre>
  
  <p>Now I want to modify it to make the added class removed from the <code>.thing</code> element immediately when its out of browser view. What do I add to code above?</p>