Correct the error code value for SVN_ERR_REPOS_CORRUPTED.
Fix the verify-keep-going test case to compare actual stdout and expected stdout.

* subversion/include/svn_error_codes.h
  Set the correct error code value.

* subversion/tests/cmdline/svnadmin_tests.py
  (verify-keep-going): Fix the error code value. Also compare actual stdout
  and expected stdout in addition to stderr comparison.


git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/verify-keep-going@1491440 13f79535-47bb-0310-9956-ffa450edef68