Function withdraw 

pub fn withdraw(
    dir: &Path,
    package: &str,
    version: &str,
    reason: &str,
) -> Result<ArchiveOutcome, String>

#2330 (D): bynk registry withdraw — the takedown of package version on the registry at dir. Sets yanked and withdrawn (reason) on its line, re-signing nothing, then deletes its archive unless another line names the same tree. Final: a withdrawn version is refused here (unless an interrupted withdrawal left its archive behind, which is then deleted), by add, by the publish API and by an un-yank.