Add an archive section for old editions

[pixup1]

Type of Issue

• Bug
• Feature Request
• Documentation
• Other

Description

Add an archive section (different from the one that is already here, that one is only for the tournaments). This would show the posters for past editions, and maybe even a little description ?

This feature was in the old website but it never got implemented in the new version. I think it's a nice way to keep a trace of the event's history.

The backend already has an entry for each previous edition, so maybe we could add new "poster" and "description" fields for all these entries.

Screenshots

This is how it looked on the old website:

Wayabck machine: link

(It could probably use a little more formatting as well.)