Return a list of virtual machine names on the minion

    CLI Example:

    .. code-block:: bash

        salt '*' virt.list_domains

def list_domains():
    '''
    Return a list of virtual machine names on the minion

    CLI Example:

    .. code-block:: bash

        salt '*' virt.list_domains
    '''
    with _get_xapi_session() as xapi:
        hosts = xapi.VM.get_all()
        ret = []

        for _host in hosts:
            if xapi.VM.get_record(_host)['is_control_domain'] is False:
                ret.append(xapi.VM.get_name_label(_host))

        return ret