i124477 set object shadow always at PPT import, it may be applied to object text
i124389 correct TextFrame layout for tables not when new text is set, but in UNdo/Redo directly for performance reasons
124514: show/hide Overlay object to highlight annotated text range according the according view option which show/hides the annotations/comments
i120201 added forcing TableLayouter to take action in table undo/redo (CellUndo)