StarkNet Node API v0.2.0

This is the 2nd release of the specification for full node API specification for Starknet nodes.

Changes

Changes since v0.2.0 RC1

1. Remove redundant 'class_hash' in the array of declared contracts
2. Add invoke receipt properties to deploy receipt
3. Change some invalid errors to not found errors
4. Add invalid block id error to get events
5. 'type' is required in transaction receipt
6. fixing schema issues