Move Clap validators to their own crate

[romac]

Or add them to https://github.com/kbknapp/clap-validators

[dtsbourg]

Not sure it's maintained, there's only one sample validator from March 2016. clap-rs/clap-validators@61a6d06

What's the advantage of moving them to another crate ?

[romac]

Not sure it's maintained, there's only one sample validator from March 2016.

Yeah I saw but since I took the idea from there, I was thinking I could contribute some of those validators to this repository. But I think you're right, as it's unmaintained we'd better build our own crate.

What's the advantage of moving them to another crate ?

Well, validators are reusable code that has nothing to do with rustysecrets, and might be useful for other projects. Also, I don't like having them in cli.rs instead of their own file, but had to do it this way because of the build-time shell completion generation (build.rs).