FR: Secure secrets storage

[raggi]

I saw the external file secrets feature, but as it doesn't support relative paths or expansions it's a pain for portability, and it still means leaving secrets in places that are trivial to steal.

How would you feel about a PR that integrates a crate like https://crates.io/crates/keyring for cross-platform secret storage and recovery?

I'd imagine adding a configuration field such as keyring = true which means to lookup a secret in the secret store, and a small piece of dialog UI for accepting and updating the keyring contents.

[casperstorm]

It has been discussed before, and I think its a good idea!