Add support for indexed (and non-indexed) Event fields types that are distinct `ValueType` or `SmallByteArray`. For example,
```nim
type
DistinctAlias = distinct array[32, byte]
MyEvent = object of Event
a {.indexed.}: DistinctAlias
b: DistinctAlias # also allowed for non-indexed fields
## The below funcs generally need to be included for ABI
## encoding/decoding purposes when implementing distinct types.
func toArray(value: DistinctAlias): array[32, byte] =
array[32, byte](value)
func encode*(encoder: var AbiEncoder, value: DistinctAlias) =
encoder.write(value.toArray)
func decode*(decoder: var AbiDecoder,
T: type DistinctAlias): ?!T =
let d = ?decoder.read(type array[32, byte])
success DistinctAlias(d)
```
1. rename helpers to testing and expose externally via `import pkg/ethers/testing`
2. Change detection of revert from `EthersError` to `JsonRpcProviderError`
3, Remove catch of `CatchableError` from revert detection as this would swallow errors. Update tests accordingly.
- `TransactionReceipt.blockHash` is optional
- Block.number is optional (in case node doesn’t return this in the event)
- Refactor confirmations waiting such that there is no polling for a receipt at the start
- Make BlockHandler and SubscriptionHandler async
- change casing of constants
- change return type checking of contract method to check for `Confirmable` instead of `?TransactionRepsonse`
- Reduce miner sleep to 10ms
- Change `wait` and `Waitable` to `confirm` and `Confirmable` to avoid conflict with chrono’s `.wait`.
- Update params on `.confirm` so that the compiler can restrict values of the `int` to `Positive` and `Natural`.
- Add `Block` and `TransactionReceipt` conversion tests to test for missing block number and block hash.
- Add tests for confirmation calculations and determining if a tx has been mined from its receipt.
- Assume that blockNumber returned from node will be null or empty string, in which case we can parse as 0 and test for that condition.
