Documentation (MKDOCS) (#1230)

Co-authored-by: Steve Richards <srichards@mirantis.com>
Co-authored-by: Mario Sarcher <msarcher@mirantis.com>
Co-authored-by: steve richards <steve.james.richards@gmail.com>
Co-authored-by: Paul Williams <pawilliams@mirantis.com>
Co-authored-by: pauljwil <pauljwil@gmail.com>

docs/custom_theme/main.html

@@ -0,0 +1,12 @@
+{% extends "base.html" %}
+
+{% block analytics %}
+  <!-- Global site tag (gtag.js) - Google Analytics -->
+  <script async src="https://www.googletagmanager.com/gtag/js?id=G-90E1JB4HW4"></script>
+  <script>
+    window.dataLayer = window.dataLayer || [];
+    function gtag(){dataLayer.push(arguments);}
+    gtag('js', new Date());
+    gtag('config', 'G-90E1JB4HW4');
+  </script>
+{% endblock %}