Merged revisions 85689 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/branches/py3k

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  r85689 | hirokazu.yamamoto | 2010-10-18 21:13:18 +0900 | 3 lines

  Issue #5117: Case normalization was needed on ntpath.relpath(). And
  fixed root directory issue on posixpath.relpath(). (Ported working fixes
  from ntpath)
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