Refine operational logging for mergeinfo.
Refine operational logging for mergeinfo.

* subversion/mod_dav_svn/reports/mergeinfo.c
  (dav_svn__get_mergeinfo_report): dlr, epg, and glasser couldn't
    figure out what "partial" meant in log action, but agreed this
    should just log the list of paths as other operations (e.g. log)
    do.  Also log the inherit value.

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