v2.0.0

This release features a number of breaking changes:

• The signature for callCC is now rank-2 to allow for any result to be discarded #74 (@jqyu)
• Functional dependencies have been added to all classes
• Newtype instances have been derived for all transformers
• ListT.scanl implementation has been fixed #72 (@DanielGronau)
• MonadReader has been split into MonadAsk and MonadReader
• MonadWriter has been split into MonadTell and MonadWriter
• ComonadEnv has been split into ComonadAsk and ComonadEnv
• MonadTrans class is now in Control.Monad.Trans.Class
• ComonadTrans class is now in Control.Comonad.Trans.Class
• ExceptT's apply and bind now behave consistently, at the cost of tightening the m constraint to Monad for the Apply and Applicative instance
• The MonadRWS class has been removed