update jshintrc to es6 and stop polyfilling for apps

.jshintrc

@@ -12,6 +12,7 @@
     "unused": true,
     "futurehostile":true,
     "browser": true,
+    "esversion": 6,
     "predef": [
         "console",
         "define",

www/common/boot2.js

@@ -54,11 +54,6 @@ define([
         };
     }
 
-    // RPC breaks if you don't support Number.MAX_SAFE_INTEGER
-    if (Number && !Number.MAX_SAFE_INTEGER) {
-        Number.MAX_SAFE_INTEGER = 9007199254740991;
-    }
-
     var failStore = function () {
         console.error(new Error('wut'));
         require(['jquery'], function ($) {

www/common/sframe-boot2.js

@@ -13,11 +13,6 @@ define([
         };
     }
 
-    // RPC breaks if you don't support Number.MAX_SAFE_INTEGER
-    if (Number && !Number.MAX_SAFE_INTEGER) {
-        Number.MAX_SAFE_INTEGER = 9007199254740991;
-    }
-
     var mkFakeStore = function () {
         var fakeStorage = {
             getItem: function (k) { return fakeStorage[k]; },