Merge pull request #96 from jamesarosen/james/addEventListener

async: use three args for addEventListener

lib/rsvp/async.js

@@ -41,7 +41,7 @@ function useMutationObserver() {
   window.addEventListener('unload', function(){
     observer.disconnect();
     observer = null;
-  });
+  }, false);
 
   return function(callback, arg) {
     queue.push([callback, arg]);