persistence of not required media on disk. Second step updated the cleanSource methods in classes that handle files on disk

Navigation palette: thumbnails isn't refeshed after application added to the page

Fixed some related issues.

Now coping creates a full copy of already created item. Copy has it's own content (like video, audio or folder) and stores original item properties (like locked, pos, size, freezed e.t.c.).

UBToolWidget API has been deactivated, there is certainly a lot of bugs, code is ugly.
Remember to fix commented sections (forgotten which ones).

This is not functional.