0.2.0

Added

• Direct chain integration which allows to connect to a real cardano-node /
  devnet; no on-chain validators though.
• Support alonzo transactions inside the Hydra Head. For now using a freeCostModel.
• Command line options --node-socket, --network-magic and
  --cardano-{signing,verification}-key to hydra-node and hydra-tui to
  configure the Cardano network access.

Changed

• Command line options of hydra-node quite significantly to distinguish hydra
  credentials from cardano credentials.
• Commit and transaction creation logic of TUI to use cardano credentials.

Removed

• ZeroMQ mock-chain executable, chain component and corresponding hydra-node
  command line options.
• ZeroMQ based network component.
• Aliases from party identifiers.

Fixed

• hydra-tui to correctly show current state when re-connecting.

Known issues

• Only no or one utxo can be committed to a Head.
• Recipient addresses to send money to in the TUI are inferred from the current
  UTXO set. If a party does not commit a UTXO or consumes all its UTXO in a
  Head, it won't be able to send or receive anything anymore.
• TUI crashes when user tries to post a new transaction wihout any UTXO
  remaining.
• Not an issue, but a workaround: The internal wallet of hydra-node requires a
  UTXO to be marked as "fuel" to drive the Hydra protocol transactions.