BIND 10 #2432: define and implement base and libdns++ version of RRsetCollection

[BIND 10 Development]

#2432: define and implement base and libdns++ version of RRsetCollection
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            Reporter:  jinmei        |                        Owner:
                Type:  task          |  vorner
            Priority:  medium        |                       Status:
           Component:  libdns++      |  reviewing
            Keywords:                |                    Milestone:
           Sensitive:  0             |  Sprint-20130108
         Sub-Project:  DNS           |                   Resolution:
Estimated Difficulty:  5             |                 CVSS Scoring:
         Total Hours:  0             |              Defect Severity:  N/A
                                     |  Feature Depending on Ticket:
                                     |  loadzone-ng
                                     |          Add Hours to Ticket:  0
                                     |                    Internal?:  0
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Comment (by jinmei):

 While working on #2433 I've noticed a few things (incorrectly
 updated #2433 with those comments, now copying them to the correct
 ticket...)

 - please add rrset_collection(,_base).h to libdns___include_HEADERS in
 Makefile.am.
 - in RRsetCollectionBase, protected things should generally be documented
 sufficiently detailed so that derived class implementor can implement
 their version from the documentation.
 - Also for iterator. And, btw, per naming convention it should be named
 something like Iterator.
 - I'd like to suggest defining another version of constructor that takes
 istream. That would be useful for tests (and probably for some other
 general cases).
 - I'd explain what kind of collection is constructed by the default
 constructor.
 - we need to define a virtual destructor in the base class.

-- 
Ticket URL: <http://bind10.isc.org/ticket/2432#comment:16>
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