docs: include google-analytics on homepage.

doc/index.html

@@ -485,6 +485,15 @@ <h2>Project Details</h2>
     <script src="_static/jquery.js"></script>
     <script src="_static/vendor/bootstrap/js/bootstrap.min.js"></script>
     <script src="_static/vendor/owl.carousel/owl.carousel.min.js"></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-29887834-3', 'auto');
+  ga('send', 'pageview');
+</script>
     <script type="text/javascript">
     $(function () {