Make all JPanels dockable?

[i-make-robots]

Is your feature request related to a problem? Please describe.
With very few exceptions all windows should be dockable.
There's no simple way make a new window that is immediately dockable.

Describe the solution you'd like
Some way for any class that handles windows to call on Modern Docking and say "here, have a new JPanel".
This probably means anyone that can produce a JPanel is part of a TabFactory known to MD.

Describe alternatives you've considered

Additional context
#312 might be a duplicate.