DNS classless support for reverse domains
    
    Now users can add reverse zones in classless form:
    0/25.1.168.192.in-addr.arpa.
    0-25.1.168.192.in-addr.arpa.
    
    128/25 NS ns.example.com.
    10 CNAME 10.128/25.1.168.192.in-addr.arpa.
    
    Ticket: https://fedorahosted.org/freeipa/ticket/4143
    Reviewed-By: Jan Cholasta <jcholast@redhat.com>