chore: version to 0.4.0

[miraclx]

Scheduled release: 31-05-2022

Notable changes:

• Updated nearcore dependencies, fixing a previous breaking change. chore: update nearcore dependencies #100
• Fixed query method error deserialization. fix: patch query response deserialization, add tests #82
• Fixed gas_price RPC method serialization. fix: gas_price RPC method serialization #73
• Reworked the JsonRpcError::handler_error method. fix: rework the JsonRpcError::handler_error method #99
• Moved auth specific logic behind a feature flag. chore: move auth-specific logic behind the default auth feature flag #55
• Added the methods::to_json() helper method for visualizing the serialization of the RPC methods. feat: add ability to serialize requests to preview server request payload #49
• Extracted all the RPC methods into their own modules instead of all being defined in the same methods.rs file. chore: decouple methods into individual fs modules #50

Aspirational:

• Exhaustively documented the client. Tracking issue for the exhaustive documentation of the jsonrpc-client #51

[miraclx]

Closing in favor of #112