Support for Conway protocol parameters

[agaffney]

A number of new params have been added. It also looks like protocol version was removed since Babbage. This will probably let us stop duplicating so much between the Conway+ ProtocolParameters and ProtocolParameterUpdate types.

https://github.com/IntersectMBO/cardano-ledger/blob/master/eras/conway/impl/cddl-files/conway.cddl

NOTE: unit_interval is handled by cbor.Rat

  , ? 25: pool_voting_thresholds ; pool voting thresholds
  , ? 26: drep_voting_thresholds ; DRep voting thresholds
  , ? 27: uint                   ; min committee size
  , ? 28: epoch                  ; committee term limit
  , ? 29: epoch                  ; governance action validity period
  , ? 30: coin                   ; governance action deposit
  , ? 31: coin                   ; DRep deposit
  , ? 32: epoch                  ; DRep inactivity period
  , ? 33: nonnegative_interval   ; MinFee RefScriptCostPerByte

pool_voting_thresholds =
  [ unit_interval ; motion no confidence
  , unit_interval ; committee normal
  , unit_interval ; committee no confidence
  , unit_interval ; hard fork initiation
  , unit_interval ; security relevant parameter voting threshold
  ]

drep_voting_thresholds =
  [ unit_interval ; motion no confidence
  , unit_interval ; committee normal
  , unit_interval ; committee no confidence
  , unit_interval ; update constitution
  , unit_interval ; hard fork initiation
  , unit_interval ; PP network group
  , unit_interval ; PP economic group
  , unit_interval ; PP technical group
  , unit_interval ; PP governance group
  , unit_interval ; treasury withdrawal
  ]