[MERGE] rip off the trailing whitespace band-aid

[Stephen J. Turnbull]

John Arbash Meinel writes:

 > Does anyone know what 'emacs' can give you to help with trailing whitespace?

What do you mean by "help"?  Do you want it prohibited?  Displayed?
Emacs to whine and moan until you fix it?

There are a bunch of whitespace modes.  `whitespace-visual-mode' will
display various kinds of whitespace with different highlighting.  I
think it's one size fits all, no special support for Python.  I think
you can probably turn off the whitespace checks you don't want.