remove kappname - unused in kf5
use CCBYSA4 - required for new docbooks
use entities dolphin, plasma
General issues to be discussed:
Probably better to go with a man page, if @elvisangelaccio agrees.
We probably need a manpage anyway, since this is a cli app. If we go with manpage only, would it show up in khelpcenter?
Yes, because khelpcenter supports also man and info pages.
Superseded by https://phabricator.kde.org/D8994