Currently when a single part is saved this gives a very bad user
experience as the user has to choose from a (single element) checkbox
list with option [OK] and [CANCEL], but to *not* save the part one has
to uncheck that part and then press [OK].

This now enhances the case of single element to asking the user with a
simple dialog and the choice to [SAVE] / [DON'T SAVE] / [CANCEL] how it
is done for the IDE with the e3 editors.