class Dnsruby::Message

===Defines a DNS packet.

RFC 1035 Section 4.1, RFC 2136 Section 2, RFC 2845

===Sections
Message objects have five sections:
In addition, each_resource iterates the answer, additional
and authority sections :

     msg.each_resource {|rr| ... }

===Packet format encoding

     Dnsruby::Message#encode
     Dnsruby::Message::decode(data)

===Additional information
security_level records the current DNSSEC status of this Message.
answerfrom records the server which this Message was received from.
cached records whether this response came from the cache.