Add a way for auditing tools to correlate S3 object calls with Hadoop FS API calls.
Initially just to log/forward to an auditing service.
Later: let us attach them as parameters in S3 requests, such as opentrace headeers or (my initial idea: http referrer header -where it will get into the log)
- ensuring the audit span is created for every public entry point. That will have to include those used in s3guard tools, some defacto public APIs
- and not re-entered for active spans. s3A code must not call back into the FS API points
- Propagation across worker threads