[Blacklight] Integrate the Blacklight service about privacy as a new module

[bgatellier]

Blacklight is a Real-Time Website Privacy Inspector created by The Markup, a nonprofit newsroom.

Their analysis solution is open-source (custom license) and is available as an NPM package: https://www.npmjs.com/package/@themarkup/blacklight-collector

⚠️ The service does not rate a webpage, but lists services.
So we need need to find a way to compile the results into a ranking (or change Heart to manage services that does not ranking, but that's another story)