New sources & configuration & docs improvements

Release highlights

• New modular architecture of the indexer
  • sources and sinks are generic and replaceable
  • oura and cardano_net sources are now supported (previously there was only oura option)
  • any other source can be used in carp provided that it implements Source trait
• Graceful shutdown for the indexer
• Carp starts using .yml files for configuration
  • allows to configure sources / sink / relays / db connection for the indexer
• Oura Source supports both Unix and Tcp connections straight away (no need to switch / hardcode as it was before)
• Docker-compose deployment upgrades:
  • detailed examples of configs
  • enriched guide in the documentation
• Dependency updates

Breaking changes

Carp indexer requires a configuration file for running since now. See the docs for detailed instructions

What's Changed

• New sources model for carp by @gostkin in #116
• Update version to 2.2.0 by @gostkin in #136

Full Changelog: 2.1.2...2.2.0