EVM: Implement basic Ethereum JSON-RPC endpoints.

[bkolad]

Description

Here is the comprehensive list of Ethereum JSON-RPC endpoints: link to the documentation. While it would be ideal to support all of them, we need to prioritize the most useful ones initially. Here is the prioritized list of endpoints (needed to deploy Uniswap-v2) that need to be implemented first:

• eth_chainId EVM: Implement eth_chainId endpoint. #877
• eth_getBlockByNumber EVM: Implement eth_getBlockByNumber endpoint.  #878
• eth_getTransactionByHash
• eth_getTransactionReceipt
• eth_call EVM: Implement eth_call endpoint. #879
• eth_sendTransaction EVM: Implement eth_sendTransaction endpoint. #880 (done for the latest block)
• eth_blockNumber EVM: Implement eth_blockNumber endpoint.  #881
• eth_getTransactionCount EVM: Implement eth_getTransactionCount endpoint. #882
• eth_gasPrice EVM: Implement eth_gasPrice endpoint. #883
• eth_feeHistory

Acceptance Criteria

Unit test for each endpoint.