Add vmhost parameter to SW.install() to support upgrading the VM Host.
Add vmhost parameter to SW.install() to support upgrading the VM Host.

Initial support for upgrading vmhost.

Juniper/py-junos-eznc,pklimai/py-junos-eznc,pklimai/py-junos-eznc,Juniper/py-junos-eznc,Juniper/py-junos-eznc,pklimai/py-junos-eznc