* WIP
* Begin converting rpc layer to use std futures and jsonrpsee
* Convert metadata to async/await
* Convert block_hash to async/await
* Convert more methods to async/await
* Remove sp_rpc
* Fix more compilation errors
* Remove connect
* Starting to convert subscription functions
* Use jsonrpsee branch from PR for public client types
* Implement subscribe events with jsonrpsee subscription
* Converting subscriptions and wait_for_block_events
* WIP converting lib methods to async
* Use shared client reference directly for rpc call
`rpc_api!` macro currently only supports RawClient (which cannot be shared).
Also supports named params only which is not currently compatible with substrate rpd which accepts only positional params.
* Use &self instead of &mut self for shared Client
* Convert submit_and_watch to async/await
* Convert more Client fns to async
* Pin some trait futures
* Add serde error
* Fix client creation
* Fix client request compiler errors
* Unify metadata errors
* Add WS handshake error variant
* Fix some more compiler errors
* Fix more compiler errors
* Convert submit_extrinsic to async
* Convert submit and submit_and_watch
* Add Send + Sync constraints
* Clone clients
* Fix EventArg conversion error
* Fix remaining warnings/errors
* Replace deny warnings with specific lints
* Infallable subscription loops
* Use jsonrpsee wss branch
* Fix example
* Start to fix up tests
* Make contracts tests compile
* Make some more tests pass
* Fix up remaining tests
* Fmt
* Use correct event storage key type
* Fix finding events
* Use master jsonrpsee
Andrew Jones