[#12] Add support for Matomo tracking

closes #12

docs/advanced/matomo.md

+# Site analytics - Matomo registration
+
+In order to track your site using Matomo web analytics you need to follow these steps.
+
+
+## Request a Matomo website
+First of all, you need to open a ticket with the [Matomo team](https://cern.service-now.com/service-portal?id=functional_element&name=web-infrastructure) requesting a Matomo website for your URL. They will reply to you with the JavaScript snippet that needs to be embedded into your site.
+
+### Method 1: Extending JavaScript
+
+1. Add to the `mkdocs.yml` file the entry:
+
+    ```
+    extra_javascript:
+      - javascripts/matomo.js
+    ```
+
+2. In the `docs/javascripts` folder, create a `matomo.js` file with the JavaScript tracking code that you can find inside the `<script>` tags that the Matomo team replied to you:
+
+    ```
+    var _paq = window._paq = window._paq || [];
+    /* tracker methods like "setCustomDimension" should be called before "trackPageView" */
+    _paq.push(['trackPageView']);
+    _paq.push(['enableLinkTracking']);
+    (function() {
+      var u="https://webanalytics.web.cern.ch/";
+      _paq.push(['setTrackerUrl', u+'matomo.php']);
+      _paq.push(['setSiteId', '[cern site id]']);
+      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);
+    })();
+    ```
+
+### Method 2: Overrides customization
+Once you obtain the JavaScript tracking code, follow [this guide](https://squidfunk.github.io/mkdocs-material/setup/setting-up-site-analytics/#custom-site-analytics) to configure the analytics for your MkDocs site.

[Michal Kolodziejski]

-

[Michal Kolodziejski]

-## Request a Matomo website
-First of all, you need to open a ticket with the [Matomo team](https://cern.service-now.com/service-portal?id=functional_element&name=web-infrastructure) requesting a Matomo website for your URL. They will reply to you with the JavaScript snippet that needs to be embedded into your site.
+## Request a Matomo website
+
+First of all, you need to open a ticket for the [Matomo team](https://cern.service-now.com/service-portal?id=functional_element&name=web-infrastructure) requesting a Matomo website for your URL. They will reply to you with the JavaScript snippet that needs to be embedded on your site.

[Michal Kolodziejski]

-### Method 1: Extending JavaScript
+### Method 1: Adding custom JavaScript code

[Michal Kolodziejski]

-      - javascripts/matomo.js
+      - js/matomo.js

[Michal Kolodziejski]

-2. In the `docs/javascripts` folder, create a `matomo.js` file with the JavaScript tracking code that you can find inside the `<script>` tags that the Matomo team replied to you:
+2. In the `docs/js` folder, create a `matomo.js` file with the JavaScript tracking code that you can find inside the `<script>` tags that the Matomo team replied to you:

[Michal Kolodziejski]

-2. In the `docs/javascripts` folder, create a `matomo.js` file with the JavaScript tracking code that you can find inside the `<script>` tags that the Matomo team replied to you:
+2. In the `docs/javascripts` folder, create a `matomo.js` file with the JavaScript tracking code that you can find inside the `<script>` tags that the Matomo team provided you with: