Proposal: Add `Generically` (or `WrappedGeneric`) newtype to GHC.Generics

[Alexis King]

As just one more data point, Rob Rix from the GitHub semantic code team has pointed out to me that their `semantic` library also includes a `Generically1` type, defined here:

https://github.com/github/semantic/blob/8c0041f1ec5a3ee9f3d0294c35220bfde209c68b/src/Data/Functor/Classes/Generic.hs#L184-L190

(They call it `Generically`, but it’s actually equivalent to the `Generically1` type from `generic-data` and serves the same purpose.)