update to new google analytics tag

Author: aurbano

.ruby-version

@@ -0,0 +1 @@
+2.5.0

_includes/scripts.html

@@ -25,17 +25,13 @@
 <script src="/js/new-age.min.js"></script>
 
 {% if site.google_analytics %}
-<script type="text/javascript">
-  var _gaq = _gaq || [];
-  _gaq.push(['_setAccount', '{{ site.google_analytics }}']);
-          _gaq.push(['_trackPageview']);
-  (function () {
-      var ga = document.createElement('script');
-      ga.type = 'text/javascript';
-      ga.async = true;
-      ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js';
-      var s = document.getElementsByTagName('script')[0];
-      s.parentNode.insertBefore(ga, s);
-  })();
+<!-- Global site tag (gtag.js) - Google Analytics -->
+<script async src="https://www.googletagmanager.com/gtag/js?id={{ site.google_analytics }}"></script>
+<script>
+  window.dataLayer = window.dataLayer || [];
+  function gtag(){dataLayer.push(arguments);}
+  gtag('js', new Date());
+
+  gtag('config', '{{ site.google_analytics }}');
 </script>
 {% endif %}