Followup to spacetelescope/PyFITS#3 ensuring that the regression test for that issue works on Python 3.

git-svn-id: http://svn6.assembla.com/svn/pyfits/branches/3.1-stable@2099 ed100bfc-0583-0410-97f2-c26b58777a21
Fixes https://trac.assembla.com/pyfits/ticket/203 with regression test

git-svn-id: http://svn6.assembla.com/svn/pyfits/branches/3.1-stable@2104 ed100bfc-0583-0410-97f2-c26b58777a21