Work in progress.  Clean build of new callback interfaces for
the object lists and hooks needed to refresh the lists when
an element is presented by a View/Edit window and the sub-window
is closed.  Rather than dealing with tracking of whether changes
have actually been applied or not, the list refreshes whenever
the window is closed no matter what was done with it.  That's not
ideal, but this *is* only a prototyping/demo GUI, not a production
system.