Adds the new linter and configures it to prevent direct error
comparisions and type assertions in favor of errors.Is and errors.As.
All current violations caught by the linter have been updated
accordingly.
* Add Yubikey PrivateKey implementation for use by Teleport clients.
- Add yubikey login logic, reusing previously stored private keys.
- Fix identity file decoding with PIV keys, which sign ecdsa certificates.
- Add libpcsclite-dev pre-req for building on linux.
- Remove unnecessary keys.Signer interface and move its functionality to keys.PrivateKey.
- Move retry and jitter utils to new api/utils/retryutils package.