Fix to deprecated message

Line 220 has a deprecated method,
\unittest_xml_reporting-1.0.3-py2.6.egg\xmlrunner\init.py:220: DeprecationWarning: BaseException.message has been deprecated as of Python 2.6

to fix this you simply need to make one little change to that line.
Original: failure.setAttribute(‘message’, test_result.err¹.message)
New: failure.setAttribute(‘message’, str(test_result.err¹))