ekmett/either — pull request #12 by clinty (2013-12-17 05:00:38+00:00)
Title: MonadBase, MonadBaseControl, and MonadTransControl instances for EitherT e

This introduces dependencies on TypeFamilies, monad-control, and transformers-base. I'm not sure if this would obviate [johnw's finallyE](https://github.com/ekmett/either/pull/6).