title: Is there an "ApplicativeIO" class?
body: <p>Is there somewhere in Hackage a typeclass analogous to <a href="http://hackage.haskell.org/package/transformers-0.4.1.0/docs/Control-Monad-IO-Class.html#v:liftIO"><code>MonadIO</code></a> but for <code>Applicative</code>s, that allows one to easily lift <code>IO</code> actions to <a href="http://hackage.haskell.org/package/transformers-0.4.1.0/docs/Data-Functor-Compose.html">"applicative composition stacks"</a>  based on <code>IO</code>?</p>
  
  <p>If such a typeclass existed, would it be made obsolete by the implementation of the <a href="http://www.haskell.org/haskellwiki/Functor-Applicative-Monad_Proposal">Applicative-Monad Proposal</a>? Does the proposal involve a relaxation on the <code>Monad</code> constraint for <code>MonadIO</code>?</p>