dogtag: search past the first 100 certificates
    
    Dogtag requires a size limit to be specified when searching for
    certificates. When no limit is specified in the dogtag plugin, a limit of
    100 entries is assumed. As a result, an unlimited certificate search
    returns data only for a maximum of 100 certificates.
    
    Raise the "unlimited" limit to the maximum value Dogtag accepts.
    
    https://fedorahosted.org/freeipa/ticket/6564
    
    Reviewed-By: Tomas Krizek <tkrizek@redhat.com>