Join the Fediverse:Proposal for new stucture

I'm trying to restructure the wiki a bit and then create more content to answer the most basic questions people have about the Fediverse.

Finished changes

• Namespaces: We now have 2 new namespaces. Draft and Archive. You can find e.g. Draft:Captions and Archive:Mastodon features explained in the new namespaces.
• Article titles: I renamed all articles that were titled "What is...?" or "What are...?" to the more simple title, e.g. Mastodon instead of What is Mastodon? (which redirects to the former though).
• Categories: I removed some categories like the "What is" category and added a few new ones, like Category:Usage.

Ongoing changes

• I'm drafting a new Fediverse article where you can find answers to basic questions in a more structured way. Draft:New Fediverse Article
• The Main page should already have a section explaining what the Fediverse is.
• I'll add redirects for all major social media platforms that lead either to the most common Fediverse replacement or to a list of Fediverse services of the same type. E.g. Twitter could redirect to Mastodon or List of microblogging services.
• I'll edit the sidebar to contain these items Main page, The Fediverse (What is it?, How do I join?, How do I use it?), This wiki (About, Navigation, Categories, Editing/Translating), For Editors, Guides & Guidelines, Todos, Special pages, Help about MediaWiki, Recent changes
• What people usually tell you about the Fediverse, Getting started with your Fediverse account, Welcome to the Fediverse Quickstart guide might be renamed or split/merged with different articles.