Port kolourpaint away from Kdeprint::createPrintDialog
Summary: This was the final step to port away from kdelibs4support.
Test Plan: The print dialog still has the 3rd widget with 2 radiobuttons like before.
Reviewers: broulik, andreagenor, tcanabrava, vkrause
Reviewed By: vkrause
Maniphest Tasks: T11576
Differential Revision: https://phabricator.kde.org/D25601