What's changed

Coordinator

• Router-side key range moves by @reshke (#29)
• Coordinator fixes by @reshke (#30, #47)
• Implement drop key ranges by @reshke (#31)
• Balancer console by @reshke (#33)
• Simple mover by @reshke (#39)
• Add sharding rules support in coordinator by @reshke (#48)
• Add drop sharding rules statement support by @reshke (#51)
• Add missing coordinator and router functionality by @reshke (#52)
• Fix bug with add key range using coordinator by @reshke (#53)

Router

• TLS config and router small refactoring by @Denchick (#38)
• Multishard feature by @reshke (#45)
• Simplify configs, add docs by @Denchick (#46)
• Fix json and toml config formats support by @Denchick (#54)
• Add simple COPY support by @Denchick and @reshke (#56, #58)
• Add target-session-attrs option to shard config by @reshke (#65)
• Online reload for router configuration by @reshke (#77)

Docs, tests

• Add regression PG-style tests by @EinKrebs by @Denchick @reshke (#43, #62, #67, #72, #73, #74)
• Add docs for coordinator, router and world by @Denchick (814622e, 6a77d9b, 2267506, #49)
• Add new test set with joins-relation queryies tests by @reshke (#63)