Addition of lenses for PParams

[lehins]

Description

Addition of EraPParams, AlonzoEraPParams and BabageEraPParams type classes with lenses that can access and manipulate both PParams and ParamsUpdate. Each type class requires implementation lenses for the PParamsHKD type, which are later used for defining specific lenses for PParams and PParamsUpdate respectfully

HKD types ShelleyPParams, AlonzoPParams and BabbagePParams now become internal, for the most part and the PParams+PParamsUpdate are the newtype wrappers around the era specific internal HKD type. All operations on PParams should be done with lenses from now on.

Other notable things in this PR:

• Fixes Ord instances for AlonzoPParams and BabbagePParams by introducing an internal `OrdExUniits type.
• Moves around To/FromJSON instances to prevent the from being orphan
• Moved CostModels into Cardano.Ledger.Alozno.Scripts from Cardano.Ledger.Alozno.PParams
• Switch all functions that accepted PParams as an argument, but only used protocol version, to accept only protocol version. Most notable examples are functions that do conditional checking on the hardfork
• Makes PoolEnv fields strict
• Adds a data type ByronEra that has an Era instance. This is done mostly for completeness, but also to allow getting protocol version from the type level. Also this allowed PreviousEra type family to be moved into Era type class.
• Moved all class definitions {EraName}Era{Type}, into the Cardano.Ledger.{EraName}.Core module. It was discussed before, but wasn't fully implemented.

Fixes #2927

Checklist

• Commit sequence broadly makes sense
• Commits have useful messages
• New tests are added if needed and existing tests are updated
• Any changes are noted in the changelog
• Code is formatted with fourmolu (which can be run with scripts/fourmolize.sh
• Self-reviewed the diff

[JaredCorduan]

This all looks amazing, thank you!

You don't have to do this, just an idea: maybe we could add a section to the CONTRIBUTING.md doc about open imports, forbidden them except for Core modules, and maybe lenses?