plan: externalise recodification rules for nominal variables and allow to add variables. Add simplified version of type_of_animals_kept.

- Plot only 50 most influential for any of the groups.
- Facet by topic (instead of colour labels)
- Arrange by most extreme v.test within each topic

MFA barycenters of supplementary categories: change selection of variables; separate by topic; decorate axes.

MFA: Colorise modalities by topic and include extra chart for cluster 5 conditionally on its existence.

Since they were taking all the protagonism.