Update roadmap for all languages

Based on !1231 (merged), which is required for this PR.

Review only commit abe37627

Updating all languages with the current roadmap, but this structure needs to be changed. It doesn't fit a multilingual website and makes literally impossible to update every language.

I already have an idea about the changes needed. It will make the roadmap scalable for all languages and easily pickable by weblate. This is now prioritized in my task list and i will get to it after i completed some works i'm working on at the moment.