Added "Control.Monad.Lift.IO" and "Control.Monad.Lift.Base", with very partial documentation.

I'm adding them now even though the documentation is incomplete as this may be my last chance to work on layers for the next couple of weeks, and is the last non-documentation change I can foresee until the 0.2 release, so I wanted to get it out there for people to be able to use while I'm away.
Added {-# LANGUAGE CPP #-} to several modules to fake INLINABLE support on older versions of GHC (with -DINLINABLE=INLINE).