Fixed a few typos I found in the process of merging changes into Astropy

git-svn-id: http://svn6.assembla.com/svn/pyfits/trunk@2190 ed100bfc-0583-0410-97f2-c26b58777a21
Make sure distribute_setup.py is included in the manifest.in.

git-svn-id: http://svn6.assembla.com/svn/pyfits/trunk@2191 ed100bfc-0583-0410-97f2-c26b58777a21
Assigning inf and nan as header values simply shouldn't be allowed for now, as this is undefined by the FITS standard (and the previous behavior was nonsensical anyways).  Later this will be allowed optionally.

git-svn-id: http://svn6.assembla.com/svn/pyfits/trunk@2192 ed100bfc-0583-0410-97f2-c26b58777a21
Added changelog entries for spacetelescope/PyFITS#11

git-svn-id: http://svn6.assembla.com/svn/pyfits/trunk@2195 ed100bfc-0583-0410-97f2-c26b58777a21