Prevent double delayed entity deletion
Prevent double delete in `inventory delete` cmd
CrashHandlerPOSIX: Exit on crash reporter exit

The crash reporter can fail to start if there is a problem with the
user's Qt setup. Avoid a hanging (possibly fullscreen) arx process when
that happens.
arx-install-data: Copy arx_handbuch.pdf if exists

This is found on the German retail CDROM.
Generalize charset conversion helpers
README: The library is called QtWidgets (plural)
Recalculate inventory arrow positions each frame

Fixes inventory bag switching, was broken in commit 94b19c.
Don't change InvCoords after initial calculation