BIND 10 #2239: change UDP/TCP/SyncUDPServer so they don't pass query message object

[BIND 10 Development]

#2239: change UDP/TCP/SyncUDPServer so they don't pass query message object
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            Reporter:  jinmei    |                        Owner:
                Type:  task      |                       Status:  new
            Priority:  medium    |                    Milestone:  New Tasks
           Component:  b10-auth  |                     Keywords:
           Sensitive:  0         |              Defect Severity:  N/A
         Sub-Project:  DNS       |  Feature Depending on Ticket:
Estimated Difficulty:  0         |          Add Hours to Ticket:  0
         Total Hours:  0         |                    Internal?:  0
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 In #2160, we changed `SyncUDPServer` so it doesn't clear the query_
 `Message` object.  In fact, it could even remove that member variable
 if it wasn't requested by the API contract.  Unfortunately we cannot
 simply remove them without making non trivial changes to `UDPServer`
 and `TCPServer` classes and the b10-resolver implementation.

 IMO, it's better to make the xxx server classes independent from
 `Message` management.  This ticket is a placeholder to do this task.
 Specifically:

 - remove the "query" parameter from the callback functions
 - remove the "query" member variables from XXX server classes
 - update b10-auth so it maintains `Message` internally (now that it's
   not given via the callbacks).  This should be easy.
 - Same for b10-resolver.  This may be a bit tricker due to the
   recursive-resume operations.

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Ticket URL: <https://bind10.isc.org/ticket/2239>
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BIND 10 Development