GA: Anonymize IPs and use https for the GA script.

docs/4.1/content/code/index.html

@@ -56,6 +56,7 @@
 <script>
   window.ga=window.ga||function(){(ga.q=ga.q||[]).push(arguments)};ga.l=+new Date;
   ga('create', 'UA-146052-10', 'getbootstrap.com');
+  ga('set', 'anonymizeIp', true);
   ga('send', 'pageview');
 </script>
 <script async src='https://www.google-analytics.com/analytics.js'></script>