Remove technical recommendations from page, summarise them in a separate website page

[matamadio]

Discussed today with @stufraser1: technical recommendations makes the uninteresting and generic majority of the page content on the unit page.
They could be removed, and insteada new "Recommendation" page linked on top bar could include a summary of those.

• @pzwsk to greenlight the proposal
• @arnaud-morvan to implement (just don't include technical recommendation from page layout; no need to remove all the db and admin part)

[matamadio]

Recommendation page was already part of docs, so it has been extended to include most content from technical recommendations: https://gfdrr.github.io/thinkhazard/drr-guidance/

[matamadio]

C2C to hide tech recomendations (least impact on code) and show a sentence with link to recomm page in docs (https://gfdrr.github.io/thinkhazard/drr-guidance/)

"For hazard management recommendations, see documentation."