stats: add matomo tracking code

Author: avivace

website/.vuepress/config.js

@@ -12,6 +12,19 @@ module.exports = {
   title: "gbdev.io",
   description: "game boy development scene",
   head: [
+    ['script', {}, `
+        var _paq = window._paq = window._paq || [];
+        /* tracker methods like "setCustomDimension" should be called before "trackPageView" */
+        _paq.push(['trackPageView']);
+        _paq.push(['enableLinkTracking']);
+        (function() {
+          var u="//stats.gbdev.io/";
+          _paq.push(['setTrackerUrl', u+'matomo.php']);
+          _paq.push(['setSiteId', '1']);
+          var d=document, g=d.createElement('script'), s=d.getElementsByTagName('script')[0];
+          g.async=true; g.src=u+'matomo.js'; s.parentNode.insertBefore(g,s);
+        })();
+    `],
     [
       "link",
       {