Use html5shiv from OSSCSN and add respond.js for older browsers media queries.

docs/_includes/header.html

@@ -13,7 +13,11 @@
 <link rel="stylesheet" href="../dist/ratchet.css">
 <link rel="stylesheet" href="../assets/css/docs.css">
 <link rel="stylesheet" href="../assets/css/pygments.css">
-<!--[if lt IE 9]><script src="http://html5shim.googlecode.com/svn/trunk/html5.js"></script><![endif]-->
+<!-- HTML5 shim and Respond.js IE8 support of HTML5 elements and media queries -->
+<!--[if lt IE 9]>
+  <script src="https://oss.maxcdn.com/libs/html5shiv/3.7.0/html5shiv.js"></script>
+  <script src="https://oss.maxcdn.com/libs/respond.js/1.4.2/respond.min.js"></script>
+<![endif]-->
 
 <link rel="apple-touch-icon-precomposed" sizes="114x114" href="../assets/img/apple-touch-icon-114x114.png">