Need to initialize the SUPR3HardenedVerify* bits in the extension pack manager too, so split it (the init code) out into a separate API.

VBoxExtPackHelperApp.cpp: Must initialize SUPLib before using it to verify 'self' on windows.

extended todo a little.

Try clean up the -_-uninst directory if it already exists. Suggest vboxmanage cleanup if it continue to fail.

Main,IPRT: Added RTR3INIT_FLAGS_UTF8_ARGV so VBoxExtPackHelperApp can stop IPRT from converting UTF-8 argument strings to UTF-8 again as ANSI. Fixes #6963.

RT_STR_TUPLE

Runtime: add an fMode parameter to RTDirCreateTemp() and adjust callers.

VBoxExtPackHelperApp: Fix typo

Main,QtGui: Implemented that hashing todo, extending it all the way to the gui for good measure.

IPRT/*: add _NO_SYMLINKS flags to certain functions

*,IPRT: Redid the ring-3 init to always convert the arguments to UTF-8.

iprt::MiniString -> RTCString.

VBoxExtPackHelperApp.cpp: another place for working around umask

VBoxExtPackHelperApp.cpp: Adjusted r69630 to restore the actual directory permissions.

VBoxExtPackHelperApp: override umask when creating directories

VBoxExtPackHelperApp.cpp: Fixed issue with non-ascii characters in the argument list on windows that prevent installing extension packs residing in directory with non-ascii names.

VBoxExtPackHelperApp.cpp: UAC popup instead of pop-under.

export