Better editing of multiparagraph texts

Issue description

Creating longer texts is currently more difficult than necessary in the Topincs form because the text is modeled usually by a topic type "paragraph" connecting n of these to another topic type "article". When editing an instance of article, the paragraphs are only present by their labels in the select boxes. Everything should be doable in the form of the article without any further navigation actions.

Developer comments

There is two problems here: 1) it would be much better, if the individual paragraphs could be edited inpage just like row adjuncts, and 2) since paragraphs can be reused over articles [14181, a clean solution] to this duality would be necessary.

How should the fact sheet look. It would be a shame, if the form would give a better view of the text that the factsheet.