Another proper random GUID

This time for Driver Class ID
Have to use x64 version of app for some pinvokes

At least SetupDiCallClassInstaller won't work on x64 machine if called
from x86 code.
Slow progress towards installing device within app

Device gets created, still need to do driver install. Prolly will have
to embed drivers for all versions with proper bitness (will have 2 vers
of app - x32 and x64), extract them to temp folder and point the
pinvoked function to that folder (to .inf file there). Later will need
to think about uninstall.