Handle OSX's md5sum -r being slightly different to GNU Coreutils

[hawkowl]

OS X's md5sum uses one space inbetween the sum and filename, not two. Since they both have two items, we can handle both by just fetching the first and last item.

[exarkun]

Some unit tests would probably be a good idea at this point.

[thijstriemstra]

There are tests for that macro already in twisted_trac_plugins/test/test_release_macro.py

[mithrandi]

It seems to me that the md5sums should be generated in -b mode, so there should be an asterisk and a space between the sum and the filename, not two spaces. Of course, this doesn't matter on Linux / OS X, but anyone trying to verify the md5sums on Windows might be unpleasantly confused.

This comment is, I suppose, not directly related to this pull request, let me know if I should file a separate issue.

[hawkowl]

okay now this should make it actually work
i don't have trac and am currently doing this from bed so will have to try the unit tests when i have time to deal with downloading trac

[thijstriemstra]

it's showing an error on the homepage now.

[glyph]

I updated the home page so as not to include the MD5 hash for now, temporarily fixing the error.

That whole "downloads" section should start with instructions to "pip install" now, shouldn't it?

[glyph]

Also, given that this is a python script, can't we just use Python's built-in hashing functions?