Upgrade dns/dnsdbq to version 2.4.0:

• Requires using an updated DNSDB API server. (2.3.0)

• To use the new features, add the following line the ~/.dnsdb-query.conf file: (2.3.0) DNSDBQ_SYSTEM=dnsdb2 or add the command-line option -u dnsdb2
  
  If you leave out that line, that command-line option, or use DNSDBQ_SYSTEM=dnsdb then dnsdbq will function as it previously did with DNSDB API version 1.

• change DEFAULT_SYS from dnsdb to dnsdb2; adapt rest of system to cope (2.4.0)

• add support to probe what pDNS systems the endpoint supports (2.4.0)

• normalize DNSDB APIv2; rename encap_bare to encap_cof; incorporate encap into pdns_system; remove all encap inequality tests (2.4.0)

Sponsored by: Farsight Security, Inc.