Added console_scripts entry points.  This also installs the original fitsdiff/fitscheck scripts alongside the generated ones.  On Windows this works fine because msys will use the sh versions by default, while cmd.exe will use the .exe versions by default. So having both is fine.  But I need to double check what the behavior is on Linux.  Also updated the script help text to explicitly use 'fitsdiff'/'fitscheck' as the name of the program rather than inferring it from the executable name--this approach works better for windows (so it doesn't show as, for example, fitsdiff-script.py).

git-svn-id: http://svn6.assembla.com/svn/pyfits/trunk@2122 ed100bfc-0583-0410-97f2-c26b58777a21
Add a changelog entry for #202

git-svn-id: http://svn6.assembla.com/svn/pyfits/trunk@2123 ed100bfc-0583-0410-97f2-c26b58777a21