Adding more instances to Kleisli: Generic, Monad, etc

This is another part of https://gitlab.haskell.org/ghc/ghc/merge_requests/644, which is presumably much less controversial: Generic (Kleisli m a b) Functor m => Functor (Kleisli m a) Applicative m => Applicative (Kleisli m a) Alternative m => Alternative (Kleisli m a) Monad m => Monad (Kleisli m a) (Alternative m, Monad m) => MonadPlus (Kleisli m a)