HEAD-1979: don't re-run core zone creation steps on every headnode.sh run HEAD-1977: new headnode.sh setup state 'import_smartdc_service_images' breaks on HNs setup before then
HEAD-1979: don't re-run core zone creation steps on every headnode.sh run
HEAD-1977: new headnode.sh setup state 'import_smartdc_service_images' breaks on HNs setup before then

joyent/sdc-headnode,kaizengarden/sdc-headnode,numericillustration/sdc-headnode,numericillustration/sdc-headnode,kaizengarden/sdc-headnode,numericillustration/sdc-headnode,joyent/sdc-headnode,joyent/sdc-headnode,kaizengarden/sdc-headnode,joyent/sdc-headnode,kaizengarden/sdc-headnode