Cardano Updates

See: #5477

This also requires setting the decentralisation parameter `ppD` to `< 1`
so pools can produce blocks as well. We set it to `minBound` which means
that the network is full decentralised.

See: #5477

This also requires setting the decentralisation parameter `ppD` to `< 1`
so pools can produce blocks as well. We set it to `minBound` which means
that the network is full decentralised.

Changelog for `cardano-node-10.7`

Add cabal-gild as part of the pre-commit hook in our Nix devShell.

Wow so much type hell, was catching missing instances for half a day, note to
self: try not to mess with instance decls

Added the following tests:

* JSON roundtrip property test
* Unit test for trying to decode an empty object `{}` for the
  `NonEmptyMap`, and an empty list `[]` for the `NonEmptySet`. These
  scenarios are expected to fail with a specific error message.

Using `pre-commit run --all-files` will now run `fourmolu`,
`cabal-gild`, `shellcheck` and `nixpkgs-fmt` on all modified files.

Did not add `hlint` for now because there are *lots* of warnings that
will take time to fix.