Enhance ipa-adtrust-install for domains with multiple IPA server
    
    As described on http://www.freeipa.org/page/V3/MultipleTrustServers,
    notice if FreeIPA server is a replica and adtrust agents contains members
    corresponding to the cifs/ services from replication partners.
    
    Only these servers will be advertised as SMB domain controllers
    
    https://fedorahosted.org/freeipa/ticket/2189