Qt5 compatibility using separate QML files

[dg0yt]

Some (or most) files might be shared, but this would probably lead to more fragility when development is done with new Qt versions.

This is the base for binary packages for Linux (Debian, Ubuntu, openSUSE, Fedora): https://software.opensuse.org//download.html?project=home%3Adg0yt&package=cloudlogoffline
(https://build.opensuse.org/package/show/home:dg0yt/cloudlogoffline) Of course not much tested yet.

[dg0yt]

Three more patches because this is the branch I use for tentative Linux packages. The packages on https://software.opensuse.org//download.html?project=home%3Adg0yt&package=cloudlogoffline use Qt 6 now where available - and where complete: Qt Positioning is missing in some early distributions of Qt 6.

• The qmlcachegen bug is probably fixed in Qt 6.7.1, but some distros are on 6.7.0.
• Websockets isn't used at all in Quick GUI AFAICS.
• The QPermission interface comes via the QPermissions header - the singular header doesn't work everywhere.

[dg0yt]

• The QPermission interface comes via the QPermissions header - the singular header doesn't work everywhere.

And in Fedora, QPermissions doesn't work either in Qt 6.5.2? But it belongs to core!

[dg0yt]

QPermissions doesn't work either in Qt 6.5.2? But it belongs to core!

https://bugreports.qt.io/browse/QTBUG-116178, fixed in Qt 6.6.