Changes for Qt6 compatibility

[ingpconci]

I modified the code for compatibility with Qt6.
I modified the Shadow Build directory in order to save the output outside the MapGraphics directory.
To use Android and iOs kit, do you need to open the MapGraphics and TestApp directly and not as subprojects
I tested the testapp with:
MSVC2019_64bit to make a Win executable on Win10
Android Clang_x86_64 to test in Android Emulator (No zoom features)
Android Clang_arm64-v8a and tested on an Huawey P10 lite Android 8 (No zoom features)
iOS XCode 13.2.1 iOs Simulator iPhone 11 Pro (No zoom features)

[ftomei]

Hi ingpconci
for event->angleDelta() I fixed more simply with event->angleDelta().y() > 0
that works in both 5.x and 6.x
I don't know, however, if this is correct for all cases