- Reordered the buttons to make it look nicer (but still make sence 
logically)
- Put some more divs with flex layouting to prevent elements moving 
unexpextedly.
- Changed color and list inputs to split-buttons. Those compone a button 
with a dropdown.
- The editor now saves the set color and  it can be applied to 
subsequent selections as well.

Before it was done with a dysfunctional hack. Now with proper extensions 
to existing (tiptap-node-)extensions.
Also reads existing style and sets select-element accordingly.

The main components are right at top level and the directories below
mimic the data structure (unit->page->section).
The toolbar is only used in dev mode and does not belong directly to the
unit view.
The TextEditor is a complex component and deserves it's own directory
even though it is used within the unit-view. Might be refactored to its
own module later.

Customized margins for paragraph elements.

Mistake while merging earlier.

The other one used some deprecated functionality. Also we have more 
control over what is happening now.

Based on TipTap which in turn is based on ProseMirror. No further assets 
are needed.