Define CPU mode none for virtual, host-model for HW cases

Fixes: #PRD-1950

Signed-off-by: Bogdan Dobrelya <bogdando@mail.ru>
Merge pull request #753 from bogdando/fix_prd1950

Define CPU mode none for virtual, host-model for HW cases
Merge pull request #671 from xarses/fix-some-quotes

Fixup some un-needed string interpolations
Find devices by partition GUID and exclude mounted devices

Facter function now uses partition GUID instead of filesystem label
to find matching devices. It also excludes already mounted devices.
This depends on https://review.openstack.org/#/c/54841/.
See also https://bugs.launchpad.net/fuel/+bug/1246513