Proposal: export more from Data.Kind

Hello, I'd like to export TYPE, RuntimeRep(..), Multiplicity(..) from Data.Kind. (Multiplicity is the Linear Haskell type - One and Many.) Currently you have to import GHC.Exts / GHC.Types which conflicts with Safe Haskell. I think both levity and linearity polymorphism should be available under Safe Haskell. Data.Kind already contains Constraint and Type. -Krzysztof