Added RequireJS. Bug: poll example doesnt work. The JS Poll() constructor is not being called.

common/lib/xmodule/xmodule/js/src/poll/poll.js

 window.Poll = function (el) {
+    console.log('one');
     RequireJS.require(['PollMain'], function (PollMain) {
+        console.log('two');
         $(el).children('.poll').each(function (index, value) {
+            console.log('three');
             PollMain.initialize($(value));
         });
     });

common/lib/xmodule/xmodule/js/src/poll/poll_main.js

@@ -88,6 +88,8 @@
 'initialize': function (element) {
     var _this, prevPollObj;
 
+    console.log('four');
+
     if (element.attr('poll_main_processed') === 'true') {
         // This element was already processed once.
         return;

lms/envs/common.py

@@ -386,7 +386,10 @@ courseware_js = (
     sorted(rooted_glob(PROJECT_ROOT / 'static', 'coffee/src/modules/**/*.coffee'))
 )
 
+# 'js/vendor/RequireJS.js' - Require JS wrapper.
+# See https://edx-wiki.atlassian.net/wiki/display/LMS/Integration+of+Require+JS+into+the+system
 main_vendor_js = [
+  'js/vendor/RequireJS.js',
   'js/vendor/jquery.min.js',
   'js/vendor/jquery-ui.min.js',
   'js/vendor/jquery.cookie.js',