Return a list of IPs of the nameservers for ``domain``

    If 'resolve' is False, don't resolve names.

    CLI Example:

    .. code-block:: bash

        salt ns1 dnsutil.NS google.com

def NS(domain, resolve=True, nameserver=None):
    '''
    Return a list of IPs of the nameservers for ``domain``

    If 'resolve' is False, don't resolve names.

    CLI Example:

    .. code-block:: bash

        salt ns1 dnsutil.NS google.com

    '''
    if _has_dig():
        return __salt__['dig.NS'](domain, resolve, nameserver)

    return 'This function requires dig, which is not currently available'