Add telemetry (Google or Other)

[soub4i]

Greeting

This is more about brainstorming the idea of adding telemetry tools for tracking a users' activities and preferences by GTM or Facebook Pixel

check these references:

https://www.gatsbyjs.com/plugins/gatsby-plugin-facebook-pixel

https://www.gatsbyjs.com/plugins/gatsby-plugin-google-tagmanager/

https://tagmanager.google.com/

[soub4i]

@aboullaite @yjose @soufianelf