Minor wording and whitespace cleanups

[unixorn]

• Removed trailing whitespace from lines
• Minor wording tweaks

Thanks for collecting this information, it looks like it will be very helpful as I start transitioning my code to Python 3.

[arogozhnikov]

Thanks, Joe! Just in case - are there potential problems with trailing spaces?

[unixorn]

They're just untidy. At work we don't like them, so my editor is configured to clean them automagically and since I was in the file anyway, I let it clean them up. 😄