New unit test for svn_path_check_valid, test some paths with and without  control characters.
New unit test for svn_path_check_valid, test some paths with and without 
control characters.

* subversion/tests/libsvn_subr/path-test.c
  (test_path_check_valid): New function
  (test_funcs): add the new unit test.

git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@861713 13f79535-47bb-0310-9956-ffa450edef68

YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion,wbond/subversion,wbond/subversion,YueLinHo/Subversion,wbond/subversion,wbond/subversion,wbond/subversion,YueLinHo/Subversion,wbond/subversion,YueLinHo/Subversion,YueLinHo/Subversion