We tend to use lower-case filenames. Let's do it for these files
as well. Simple search & replace.
Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>
In the future we might want to use undo-commands for mobile as
well (even if not implementing undo).
Therefore, move the undo-command source from desktop-widgets
to their own commands top-level folder.
Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>