Proposal: Move some functions from Control.Monad to Data.List

Specifically: filterM, mapAndUnzipM (unless we can sensibly and efficiently generalize it from lists to arbitrary Functors or at least Traversables, which looks like it might be possible), zipWithM, zipWithM_, replicateM, replicateM_ These functions all have to do with monads, yes, but they're about using monads with lists. Some other types are perfectly capable of doing similar things with monads. David the Feuer