Revert "onion-tunnel: Let the parser return a `Result<>`"
This reverts commit d32b9340.
Unfortunately, !291 (merged) introduced a type change away from Option<>
types
to Result<>
types.
While they are very nice for testing, they now report many false positives, due to the fact that the previous functions were designed in a fashion to return both: None in case of None, as well as in the case of an error.
I would still enjoy fixing this issue in the future, but it would
require either a re-design of core functionality of this module, or the
introduction of a Result<Option<ParseResult>, ParseError>
which is a
not so beautiful type in my opinion.
cc @ahf