* [qt] Updating CMake project files for Qt6
* [qt] Updating non-test projects for Qt6 and msvc2019
* [qt] Test fixes for Qt6 and msvc2019
* [qt] Link whole test archive for Qt and msvc2019
* [qt] Fixing Qt6 headless backend renderer
* [qt] Fixes for test failures
* [qt] Expression and style parser test fixes
* [qt] Backwards compatibility with Qt5 and Qt6
Minimum version is Qt 5.4 due to use of QOpenGLWidget
* [qt] LLVM is no longer required for a Windows build
* [msvc] msvc2019 fixes for maplibre
* Update test/storage/offline_database.test.cpp
Co-authored-by: Tadej Novak <tadej@tano.si>
* Vector + const is not standard C++
Co-authored-by: Tadej Novak <tadej@tano.si>