fix an animation glitch

If a push led to a fall, the fall could join before the fall animation
completed.

jelly.coffee

@@ -135,7 +135,11 @@ class Stage
     names = ['transitionend', 'webkitTransitionEnd']
     end = () =>
       @dom.removeEventListener(name, end) for name in names
-      cb()
+      # Wait one call stack before continuing.  This is necessary if there
+      # are multiple pending end transition events (multiple jellies moving);
+      # we want to wait for them all here and not accidentally catch them
+      # in a subsequent waitForAnimation.
+      setTimeout(cb, 0)
     @dom.addEventListener(name, end) for name in names
     return
 

jelly.js

@@ -124,7 +124,7 @@
           name = names[_i];
           _this.dom.removeEventListener(name, end);
         }
-        return cb();
+        return setTimeout(cb, 0);
       };
       for (_i = 0, _len = names.length; _i < _len; _i++) {
         name = names[_i];