Fix a few warnings, among which a circular require

Hi people @savonrb,

I run across a few warnings when looking at [a Travis-ci build][origin]. None of them [did the build fail][so], but if you want to fix them, here is a little contribution.

  [origin]: https://travis-ci.org/the4dpatrick/possible-email/jobs/32727448
  [so]: https://stackoverflow.com/questions/25342090/why-is-travis-ci-build-failing/26216824#26216824

Regards!