templates/layout: Add Inria matomo (piwik) tracking code
Add matomo tracking code in base layout.html
template.
As I could not create new websites on the Inria Matomo Web UI (even if I have the admin rights), I added archive.so and docs.so subdomains on the current declared softwareheritage.org website.
The diff also contains two other commits related to declaring license info
for the newly loaded matomo.js
script.
Related to #2762 (closed)
Migrated from D4451 (view on Phabricator)