Add forgotten import.
Undo tuple arguments to email module.

We thought for some reason there was this 'tuple' interface where you could
pass in the headers declaring their encoding.. but, it just didn't work.  When
I deployed this, it complained everywhere that it expected strings -- not
tuples.
Merge pull request #33 from fedora-infra/feature/further-email-fixes

Undo tuple arguments to email module.