OS-1851 + OS-1730 VM.reboot should wait until zone is rebooted before returning.
OS-1894: Warn, but do not crash, if metadata information is not present
OS-1229 / smartos-live#173 expose validate command via vmadm (thanks MerlinDMC)
OS-1229 fix case where brand is undefined in validate.
OS-1789 set refreservation to prevent overprovisioning KVM disks.