WIKI: Footnotes and auto-Contents features

WIKI needs footnotes feature, just like the actual WIKI (built on MediaWIki)

This should NOT use shortcodes, but rather a button in the toolbar, get a popup with fields, this then adds a footnote at the bottom.

Just like the real WIKIPEDIA.

It also needs an automatical content listing, based on headline of a certain size.

In 3 words, WIKI should be “more like Wiki!”