Trevis Elser authored May 29, 2022 and Marge Bot committed Aug 10, 2022

Adding a 'Status' field with a few values:
- Deprecated
- Experimental
- InternalUseOnly
- Noting if included in 'GHC2021', 'Haskell2010' or 'Haskell98'

Those values are pulled from the existing descriptions or elsewhere in
the documentation.

While at it, include the :implied by: where appropriate, to provide
more detail.

Fixes #21475