Patch for issue 2264 - svn client and server enhancement to send multiple
locks over ra_svn. Test #22 in lock_tests.py covers this scenario.

* subversion/include/svn_ra_svn.h
  (svn_ra_svn_handle_failure_status): New function pulled out of
  svn_ra_svn_read_cmd_response to allow lower-level handling of
  cmd response.
* subversion/libsvn_ra_svn/marshal.c
  (svn_ra_svn_handle_failure_status): New function.
  (svn_ra_svn_read_cmd_response): Refactored to call
  svn_ra_svn_handle_failure_status.
* subversion/libsvn_ra_svn/client.c:
  (svn_ra_lock): New function implementing 'lock-many' verb
  (svn_ra_lock0): Old svn_ra_lock function, now the fallback for the
  'lock' verb.
  (svn_ra_unlock): New function implementing 'unlock-many' verb
  (svn_ra_unlock0): Old svn_ra_unlock function, now the fallback for the
  'unlock' verb.
* subversion/libsvn_ra_svn/serve.c:
  (lock_many): New function
  (unlock_many): New function
  (main_commands): Added new verbs and corresponding function pointers.