Add google analytics

Auditors: alpert

index.html

@@ -86,6 +86,14 @@ f(x) = \int_{-\infty}^\infty
     <script type="text/javascript">
       startup();
     </script>
+    <script>
+        (function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
+        (i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),
+        m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)
+        })(window,document,'script','//www.google-analytics.com/analytics.js','ga');
+        ga('create', 'UA-54842501-1', 'auto');
+        ga('send', 'pageview');
+    </script>
   </body>
 </html>