PATCH: nslookup: implement human readable ttl view in debug mode

Before:

   AUTHORITY RECORDS:
    ->  l.google.com
        type = SOA, class = IN, dlen = 38
        ttl = 60 (60 secs)
        primary name server = ns1.google.com
        responsible mail addr = dns-admin.google.com
        serial = 
        refresh = 900 ()
        retry = 900 ()
        expire = 1800 ()
        default TTL = 60 ()

After:

   AUTHORITY RECORDS:
    ->  l.google.com
        type = SOA, class = IN, dlen = 38
        ttl = 60 (1 min)
        primary name server = ns1.google.com
        responsible mail addr = dns-admin.google.com
        serial = 613150094
        refresh = 900 (15 mins)
        retry = 900 (15 mins)
        expire = 1800 (30 mins)
        default TTL = 60 (1 min)