DNS: Consolidate DNS RR types in API and schema
    
    * Remove NSEC3, DNSKEY, TSIG, TKEY, TA records from API:
        These records never worked, they dont have attributes in schema.
        TSIG and TKEY are meta-RR should not be in LDAP
        TA is not supported by BIND
        NSEC3, DNSKEY are DNSSEC records generated by BIND, should not be
        in LDAP.
        *! SIG, NSEC are already defined in schema, must stay in API.
    
    * Add HINFO, MINFO, MD, NXT records to API as unsupported records
        These records are already defined in LDAP schema
    
    * Add schema for RP, APL, IPSEC, DHCID, HIP, SPF records
        These records were defined in IPA API as unsupported, but schema definition was
        missing. This causes that ACI cannot be created for these records
        and dnszone-find failed. (#5055)
    
    https://fedorahosted.org/freeipa/ticket/4934
    https://fedorahosted.org/freeipa/ticket/5055
    
    Reviewed-By: Martin Babinsky <mbabinsk@redhat.com>
    Reviewed-By: Petr Spacek <pspacek@redhat.com>