Proposal: Add Peano numbers to base

[M Farkas-Dyck]

I have seen these redefined many times now. Examples:
https://hackage.haskell.org/package/numericpeano-0.2.0.0/docs/Numeric-Peano.html#t:Nat
https://hackage.haskell.org/package/numeric-prelude-0.4.2/docs/Number-Peano.html#t:T
https://hackage.haskell.org/package/type-fun-0.0.1/docs/TypeFun-Data-Peano.html#t:N
https://hackage.haskell.org/package/number-0.1.1.0/docs/Data-Number-Peano.html#t:Nat
https://hackage.haskell.org/package/Peano-0.0.4/docs/Data-Peano.html#t:Peano

I often see them used as DataKinds. Too, operations on them can be
lazy, which is sometimes useful.

I filed a ticket: https://ghc.haskell.org/trac/ghc/ticket/11402

Discussion period: 2 weeks