Split mithril-common crate - Phase 2

[jpraynaud]

Why

We want to implement the phase 2 of the split of the mithril-common crate and delegate some of its responsibilities to new crates.

What

Split responsibilities to new crates:

• Mithril era
• Mithril ticker
• Cardano node internal database
• Cardano node mini protocols
• Web test tools (Test HTTP server and API spec)

How

• Mithril Era:
  • Create a new crate internal/mithril-era
  • Move mithril-common/era to src
  • Except for mithril-common/era/supported_era.rs which is moved to mithril-common/entities
• Mithril ticker:
  • Create a new crate internal/mithril-ticker
  • Move mithril-common/ticker_service.rs to src
• Cardano node internal database:
  • Create a new crate in internal/cardano-node/mithril-cardano-node-internal-database
  • Move mithril-common/digester to src/digester
  • Move digester/immutable_file_observer.rs in src
  • Move digester/dummy_cardano_db.rs in src/test
  • Move digester/immutable_file.rs to src/entities
  • Move digester/ledger_file.rs to src/entities
  • Add the publication of the crate on crates.io
• Cardano node chain:
  • Create an new crate in internal/cardano-node/mithril-cardano-node-chain
  • Move mithril-common/chain_observer to src
  • Move mithril-common/chain_reader to src
  • Move mithril-common/cardano_chain_scanner to src and rename it to chain_scanner
  • Move entities from src/chain_reader and src/chain_scanner to an src/entity module (ChainScannedBlocks, ScannedBlock, RawCardanoPoint, ChainBlockNextAction)
  • Web test tools (Test HTTP server and API spec):
    • Create new crates in internal/tests/mithril-api-spec and internal/tests/mithril-test-http-server
    • Remove the dependency to SupportedEra in APISpec and replace it with a String
    • Move mithril-common/test_utils/apispecs.rs to mithril-api-spec/src
    • Move mithril-common/test_utils/test_http_server.rs to mithril-test-http-server/src
• Remove the unnecessary features in mithril-common