Update log package with fields & file log, and update constants in the
repository code to be MixedCase.

resolves #91, resolves #92, resolves #95

- Update GHA lint.yml increasing timeout time to avoid GHA Lint errors
- Update common.BatchNum & common.Idx & common.Nonce usage in StateDB
- Add abstraction method of processTxs to StateDB
    - Which will be used by Synchronizer & BatchBuilder