Issues:
- an issue with DOM replacement during the update sequence...
    - kills draggable...
        the main list is dragable but after render it does not work.
    - messes with buttons on nested lists...
        to reproduce:
            open: B/C (copy path, then paste to dialog)
            collapce...
                - B is hidden fully
            recover by collapsing B then expanding
                - now everything is working but buttons are not drawn
- who is responsible for drawing? ...parent or child?
    ...this might be related to the above issue (case #2)


ToDo:
- partial render for long lists...
- mode to render paths flat (a-la browse-walk.js) 
- interactive path element...
- search -- flat/deep
- migrate constructors from browse.js...