Add search to docs

Closes: #295

website/site/templates/fathom.html

@@ -0,0 +1,15 @@
+<!-- Fathom - simple website analytics - https://github.com/usefathom/fathom -->
+<script>
+ (function(f, a, t, h, o, m){
+     a[h]=a[h]||function(){
+         (a[h].q=a[h].q||[]).push(arguments)
+     };
+     o=f.createElement('script'),
+     m=f.getElementsByTagName('script')[0];
+     o.async=1; o.src=t; o.id='fathom-script';
+     m.parentNode.insertBefore(o,m)
+ })(document, window, '//webstats.daheim.site/tracker.js', 'fathom');
+ fathom('set', 'siteId', 'OGJDF');
+ fathom('trackPageview');
+</script>
+<!-- / Fathom -->