[Peras 5] Adapt the HFC time translation layer for Peras

[tbagrel1]

Fixes tweag/cardano-peras#65

Changes

• Changes in the HFC types:
  • EraParams now keeps track of an optional Peras round length.
  • Bound now keeps track of an optional Peras round number.
  • In the Serialise instances for EraParams and Bound, the encoders generate different CBOR depending on whether of not the Peras-relate components are present. The decoders act differently depending on the length of the CBOR list.
  • The EraSummary, while not modified directly, is now Peras-aware via EraParams and Bound:
    • in a valid summary, Peras round length must divide the epoch size. See the changes in EraSummarys haddock and in invariantSummary's implementation.
• Changes in the HFC time translation queries:

  • Two new top-level queries are exposed from Ouroboros.Consensus.HardFork.History.Qry:

    perasRoundNoToSlot :: PerasRoundNo -> Qry SlotNo
    slotToPerasRoundNo :: SlotNo -> Qry PerasRoundNo

  • add a roundtrip test that ensures that converting Peras round number to a slot and then back is an identity is added into the Test.Consensus.HardFork.Summary module.

  • add a Peras-specific test into Test.Consensus.HardFork.History module.

Suggested review order

Even though this PR affects many files, the bulk of the changes is localised. I suggest the following review order:

• First review the datatype and codec changes in ouroboros-consensus/Ouroboros/Consensus/HardFork/History/EraParams.hs and ouroboros-consensus/src/ouroboros-consensus/Ouroboros/Consensus/HardFork/History/Summary.hs
• Proceed to review the time translation query changes in ouroboros-consensus/src/ouroboros-consensus/Ouroboros/Consensus/HardFork/History/Qry.hs
• Then review the newly added tests in consensus-test/Test/Consensus/HardFork/History.hs and consensus-test/Test/Consensus/HardFork/Summary.hs