Remove piwik code that references defunct URLs (#4522)

Author: kfranqueiro

_includes/waiscript.html

@@ -8,22 +8,3 @@
   var translationStrings = {}; /* fix WAI JS */
 </script>
 <script src="https://www.w3.org/WAI/assets/scripts/main.js"></script>
-{% # Matomo %}
-<script>
-  var _paq = _paq || [];
-  /* tracker methods like "setCustomDimension" should be called before "trackPageView" */
-  _paq.push(["setDoNotTrack", true]);
-  _paq.push(['trackPageView']);
-  _paq.push(['enableLinkTracking']);
-  (function () {
-    var u = "//www.w3.org/analytics/piwik/";
-    _paq.push(['setTrackerUrl', u + 'piwik.php']);
-    _paq.push(['setSiteId', '328']);
-    var d = document, g = d.createElement('script'), s = d.getElementsByTagName('script')[0];
-    g.type = 'text/javascript'; g.async = true; g.defer = true; g.src = u + 'piwik.js'; s.parentNode.insertBefore(g, s);
-  })();
-</script>
-<noscript>
-  <p><img src="//www.w3.org/analytics/piwik/piwik.php?idsite=328&amp;rec=1" style="border:0;" alt=""></p>
-</noscript>
-{% # End Matomo Code %}