Use craft on appveyor
This will use the well maintained packages from Craft.
It will reduce the maintenance cost for providing a Windows installer.
Additionally we now use up to date binaries built exactly for this compiler,
so we no longer depend on 33dparty openssl binaries etc.
Using and deploying KDE Framework 5 libaries on Windows is also possible now.
This build provides KDE Sonnet
Find out more about Craft: https://community.kde.org/Craft
Contribute to the Quassel blueprint:
https://github.com/KDE/craft-blueprints-kde/blob/master/qt-apps/quassel/quassel.py
Closes GH-312.