BIND 10 #2750: support DomainTree::remove()

[BIND 10 Development]

#2750: support DomainTree::remove()
-------------------------------------+-------------------------------------
            Reporter:  jinmei        |                        Owner:  muks
                Type:  task          |                       Status:
            Priority:  medium        |  reviewing
           Component:  data source   |                    Milestone:
            Keywords:                |  Sprint-20130917
           Sensitive:  0             |                   Resolution:
         Sub-Project:  DNS           |                 CVSS Scoring:
Estimated Difficulty:  7             |              Defect Severity:  N/A
         Total Hours:  0             |  Feature Depending on Ticket:
                                     |  shared memory data source
                                     |          Add Hours to Ticket:  0
                                     |                    Internal?:  0
-------------------------------------+-------------------------------------

Comment (by muks):

 I'm blocked on fixing this ticket as I need clarification on whether empty
 nodes are to be deleted upwards in the forest if the `DomainTree` is
 constructed to return empty nodes. In this case, its constructor argument
 name would also likely have to be changed as it's very `find()`-specific
 currently.

 Just removing empty nodes at the tree can also get rid of intentionally
 added empty nodes, so this needs clarification.

-- 
Ticket URL: <http://bind10.isc.org/ticket/2750#comment:16>
BIND 10 Development <http://bind10.isc.org>
BIND 10 Development