[KStopmotion] CMake branch ready to be merged

[Christoph Grüninger]

Hi KStopmotion enthusiasts,
hello Tim,

I think my work on CMake advanced enough to be merged. I want to give 
everybody a chance to review and ask for improvements. Especially, 
because I deprecated the support for qmake.
Please indicate, if you need more time to have a serious look. But 
comments are also welcome after I merged my branch to master

Merge request #1.
https://invent.kde.org/multimedia/stopmotion/-/merge_requests/1

Bye
Christoph

-- 
L'enjeu est de bâtir la France de nos enfants,
pas de ressasser la France de notre enfance.
                        [Emmanuel Macron, 2022]