Build on windows: fixes are ready for review

[Zoltan Padrah]

Hi,

I have prepared a set of fixes to make KTechLab build with MSVC 2019
and run on Windows, using KDE Craft :

https://invent.kde.org/sdk/ktechlab/-/merge_requests/22

Reviewers are welcome :-)

Here is a guide to KDE craft:

https://community.kde.org/Craft

The next step is to create a package of KTechLab for Windows.

Have fun,

 Zoltan