Added new XFail test for issue 2578.
Added new XFail test for issue 2578.

* subversion/tests/cmdline/switch_tests.py
  (relocate_and_propset): New test, checks that a propset 
   on an outdated folder fails on a relocated wc.
  (is_this_dav): New function, tests if we run ra_dav tests.
  (test_list): added relocate_and_propset test, XFails  
   when tests are run over ra_dav.

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