Add sanity checks for use of --ca-subject and --subject-base
    
    Print an error and terminate if --ca-subject or --subject-base are
    used when installing a CA-less master or when performing standalone
    installation of a CA replica.
    
    Part of: https://fedorahosted.org/freeipa/ticket/2614
    
    Reviewed-By: Jan Cholasta <jcholast@redhat.com>