#7 closing child windows

[Jeanne C. Otten]

It would be nice if when the user closes a data entry
window using the X button, GEMCat would
automatically close all the "child" windows that had
been opened from that main data entry window.

Now, for example, the user can open the language data
entry window, then click RFC1766 to open the list of
languages, then click X to close the language data entry
window, and the window containing the list of languages
stays open. I haven't checked every window, but I've
observed this behavior on several, so I suspect it's
consistent across all windows.