Release 0.31.0. * New functionality - `sq key subkey add` allows to create and add a new subkey to an existing certificate. - The functionality of `sq-keyring-linter` is now available as `sq keyring lint`. - The new subcommands `sq key revoke`, `sq key subkey revoke` and `sq key userid revoke`, allow writing to a file using the `--output` option. * Notable changes - The `--keyring` option is now global and can be specified anywhere when calling `sq`. * Deprecated functionality - The `--expires` and `--expires-in` options used in various subcommands are deprecated in favor of the unifying `--expiry`. - `sq key generate --export FILE` is deprecated in favor of the more generic `sq key generate --output FILE`. - The `sq revoke certificate` command has been renamed to `sq key revoke`. - The `sq revoke subkey` command has been renamed to `sq key subkey revoke`. - The `sq revoke userid` command has been renamed to `sq key userid revoke`.