Update Google Universal Analytics to load async (mmistakes#2079)

Author: coliff

_includes/analytics-providers/google-universal.html

@@ -1,10 +1,7 @@
 <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','https://www.google-analytics.com/analytics.js','ga');
-
-  ga('create', '{{ site.analytics.google.tracking_id }}', 'auto');
-  ga('set', 'anonymizeIp', {{ site.analytics.google.anonymize_ip | default: false }})
-  ga('send', 'pageview');
+  window.ga=function(){ga.q.push(arguments)};ga.q=[];ga.l=+new Date;
+  ga('create','{{ site.analytics.google.tracking_id }}','auto');
+  ga('set', 'anonymizeIp', {{ site.analytics.google.anonymize_ip | default: false }});
+  ga('send','pageview')
 </script>
+<script src="https://www.google-analytics.com/analytics.js" async></script>