Currently all our OpenStack Dom0 plugins are moved to os-xenapi, see https://github.com/openstack/os-xenapi/tree/master/os_xenapi /dom0/etc/xapi.d/plugins but some of them don't have any unit test, this task is to add unit test for xenhost.py. The whole test would include more than one commits. This one is for Network opts testing. Change-Id: I38940e130d2b661b770328f433b9c0ddc17e78a4