Qt on X11 does not support -name, -class, -geometry and -display parameters

Qt5 apps running on X11 have no way to set the settings that Qt4 apps set with "-name", "-class" and "-geometry".
Please add a way to change those settings in a Qt5 application so that users can make full use of their window managers
again.

Original description:

Qt5 apps running in X11 do not support the -name parameter to override the window name available in all other X11 apps (incl. Qt4 apps!).

I am not aware of any way to work around this limitation. This makes integrating Qt5 apps into existing X11 environments harder.