Apply the ordering rules to __all__

[tlocke]

Hi, I'm a great fan of flake8-import-order, thanks for working on it :-). My suggestion is to apply the same ordering rules to the __all__ module attribute. Would that be a good idea?

[sigmavirus24]

In #163 we discuss that this project is vaguely under a feature-freeze. I don't have opinions on whether __all__ should be ordered or not but I'm not sure it'll be implemented by this project either way

[tlocke]

Okay, I'll close this issue then. Btw, I wrote https://github.com/tlocke/flake8-alphabetize to do the sorting of __all__ as well as sorting imports.