[DOC RFE] CLI to support attached file streams

This entry tracks the addition of a support for attached files in CLI operations,

Operation arguments of type INT and annotated with attached-stream and filesystem-path must be attached to the Operation.
Users will not deal directly with streams, but with file paths.

The CLI must discover such arguments and:
1) Propose completion by looking up the file system
2) Replace the path by a stream index
3) Send the File streams as attachements

This must be supported both in batch and non batch mode.