Merge pull request #555 from ashawley/jquery-cdn

Use Google CDN for jQuery 1.8.3

Author: SethTisue

_includes/footer.html

@@ -52,7 +52,7 @@
     <script src="{{ site.baseurl }}/resources/js/vendor/prettify/lang-scala.js" type="text/javascript" ></script>
 
     <!-- jquery js -->
-    <script src="{{ site.baseurl }}/resources/js/vendor/jquery-1.8.3.min.js" type="text/javascript" ></script>
+    <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js" integrity="sha384-lifoBlbdwizTl3Yoe612uhI3AcOam/QtWkozF7SuiACaf5UJl5reOYu4MigVxrCH" crossorigin="anonymous"></script>
     <script src="{{ site.baseurl }}/resources/js/vendor/jquery.stellar.min.js" type="text/javascript" ></script>
 
     <!-- modernizr js -->