next step is to:
1. change back any ethers var names that were changed for serialization purposes, eg `from` and `type`
2. move the json util to its own lib
- signer procs raise SignerError, provider procs raise ProviderError
- WalletError now inherits from SignerError
- move wallet module under signers
- create jsonrpo moudle under signers
- bump nim-json-rpc for null-handling fixes
- All jsonrpc provider tests passing, still need to fix others
json-rpc now requires nim-json-serialization to convert types to/from json. Use the nim-json-serialization signatures to call the json serialization lib from nim-codex (should be moved to its own lib)
Based on ethers.js's queryFilter, allows querying of past contract events, by querying the logs for a contract's event topic.
* queryFilter to query past logs
* Allow querying of past block log events
* Can query by block number or block hash
Allows specified number of transaction confirmations to be awaited before a transaction is considered finalised. Polls for a transaction receipt then listens for new blocks and calculates the number of blocks between the receipt and the new block.
Notes
1. Only works with websockets currently
2. Replaced transaction not supported yet
