Allow svn_opt_revision_working as svn_opt_revision_t parameter values to svn_client_cat2().
Allow svn_opt_revision_working as svn_opt_revision_t parameter values
to svn_client_cat2().

* subversion/libsvn_client/cat.c
  (svn_client_cat2): Allow svn_opt_revision_working for PEG_REVISION
   and REVISION.

Patch by: Stefan Küng <tortoisesvn@gmail.com>

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