tools: add xenalyze

This merges xenalyze.hg, changeset 150:24308507be1d into tools/misc
to have all in one place.

Signed-off-by: Olaf Hering <ohering@suse.de>
xenalyze: hvm_emul

Signed-off-by: Olaf Hering <ohering@suse.de>