Clean up: moving deprecated components to méli-mélo

[Garneauma]

This is a clean up PR to deprecate some demoted components and move some already deprecated components to the experimentation section.

The following components/templates have been deprecated:

• Follow us variation, use GC Follow us variation instead
• Page details version 3.0 and 3.1, use Page details version 3.2 instead
• Theme and Topic template version 1, use Topic template version 2.1 instead
• Footer version 6.0, use Footer version 7.0 instead

The following components/theme have been moved to the experimentation section:

• Chat wizard
• Background image heading
• Light warning alert icon
• Pink day theme

Note: the Footer version 1 through 5 working examples have been removed from the codebase as they have been deprecated from more than a year.

[duboisp]

Partial and incomplete review, I only checked the follow-us deprecation

[duboisp]

Je pensais que les fonctionnalités provisionnelles retiré seraient tous contenu dans "deprecated". La raison principal de leur déplacement c'est parce qu'il y a eu aucune action récente démontrant l'intérêt de les stabiliser officiellement.

Aussi, il faudrait écrire une petit note pour la migration des éléments deprecated.

[duboisp]

Partial review.

We will need a note that those image file are deprecated and are going to removed from our distribution.

• x-blue-line.png

[duboisp]

Partial review

[duboisp]

A few little content adjustment and some change for the CSS copied over the deprecated css file.

[duboisp]

Reviewed and tested locally. Everything look good.

@ouafaaetta note this PR do impact a lot of component/feature and provisional feature. Take the time to get the full list.

This is major change as it mark a few component as "Deprecated" and it remove the support for the old site footer which was deprecated a year and half ago.