Change facter variable format

since facter variables are set at top scope, we can prefer "$::" to make
it explicit:
  * $operatingsystem => $::operatingsystem

Change-Id: I30a08e72182feae6f416cda96555d45d43dcc933
Merge "Change facter variable format"
Merge git://github.com/puppetlabs/puppetlabs-openstack