Add a '--skip-revprop' option to 'svnrdump load' to allow loading dumps to
a repository that allows changing most revprops, but not svn:author and
svn:date.

* subversion/svnrdump/load_editor.c
  (parse_baton): Add variable.
  (set_revision_property): Filter read revprops.
  (close_revision): Don't set svn:date and svn:author when filtered.
  (svn_rdump__load_dumpstream): Add argument.

* subversion/svnrdump/svnrdump.c
  (svn_svnrdump__longopt_t): Add option.
  (svnrdump__cmd_table): Enable option on "load"
  (svnrdump__options): Document option.
  (opt_baton_t): Add variable.
  (load_revisions,
   load_cmd): Update caller. Add argument.
  (sub_main): Parse new argument. Set new baton variable.
* subversion/svnrdump/svnrdump.h
  (svn_rdump__load_dumpstream): Add argument.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1580866 13f79535-47bb-0310-9956-ffa450edef68