add mkAsync function

www/common/common-util.js

@@ -2,6 +2,15 @@
 define([], function () {
     var Util = window.CryptPad_Util = {};
 
+    Util.mkAsync = function (f) {
+        return function () {
+            var args = Array.prototype.slice.call(arguments);
+            setTimeout(function () {
+                f.apply(null, args);
+            });
+        };
+    };
+
     // If once is true, after the event has been fired, any further handlers which are
     // registered will fire immediately, and this type of event cannot be fired twice.
     Util.mkEvent = function (once) {