upgrade/replace addon for Plone 5 and develop export/import migration process: collective.easyslider 1.4.1

[paregorios]

This addon is active in our current build. Our home page slider depends on it. We will need it to work, and all current settings/content properly migrated under 5.1.

[alecpm]

This add-on is very out of date and will probably require replacement. I do see that someone has created a "Plone 6" branch of this add-on, but I have no idea what state it might be in. Last official release was in 2014. It's not clear what an equivalent add-on might be, but collective.behavior.banner seems like it might be the closest thing. There is currently no migration for existing easysliders that I am aware of, so this would need to be developed as part of the export/import migration process.

[skleinfeldt]

@paregorios FWIW https://mrwweb.com/do-not-use-slideshow-for-nonprofit-websites/

(I know this advice won't be popular with some stakeholders but I had to mention it.)