Some minor headway on issue #3324 'path moved by merge but source not deleted'.
Some minor headway on issue #3324 'path moved by merge but source not
deleted'.

* subversion/libsvn_client/merge.c

  (do_directory_merge): Document a local variable whose name makes its
   purpose seem obvious, but which has some subtleties worth noting.
   Calculate the starting revision of the editor drive *after* going through
   all our issue #3067 machinations.  In other words: Remain liberal in
   what mergeinfo we record to describe a merge, but conservative in
   what we drive through the editor (e.g. don't use a starting rev that
   predates any operative changes).  The latter provides some issue #3324
   relief, see http://subversion.tigris.org/issues/show_bug.cgi?id=3324#desc5

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