If a merge target has WC mergeinfo don't merge it with mergeinfo from the repos.
If a merge target has WC mergeinfo don't merge it with mergeinfo from the repos.

Suggested By: lundblad

* subversion/libsvn_client/merge.c
  (get_wc_and_repos_merge_info): Renamed to get_wc_or_repos_merge_info().
  (get_wc_or_repos_merge_info): New (rename).  Tweak docstring.  Return WC
  merge info *or* repos merge info.
  (do_merge, do_single_file_merge): Update callers to use new function name.

jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion,jmckaskill/subversion