Slightly improve some tree conflict reason (local change) and
action (incoming change) descriptions.

* subversion/svn/cl-conflicts.c
  (local_reason_str): For merge, a missing node might actually be missing,
   not only deleted or moved away.
  (incoming_action_str): Indicate replacing node kind when describing
   incoming replacements.
   
* subversion/tests/cmdline/tree_conflict_tests.py
  (actual_only_node_behaviour): Adjust expected output.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1619777 13f79535-47bb-0310-9956-ffa450edef68