v2.1.0: Support @acheong08's unofficial ChatGPT API

We have added support for the unofficial proxy API by @acheong08. This API uses a proxy server that allows users to bypass Cloudflare protection and use the real ChatGPT. Please see Usage for more details.

For previous users, we've updated our API options. api.version is now api.type, with options browser (previously v3), official (previously v4), and unofficial. Please update your config file accordingly.

Full Changelog: v2.0.0...v2.1.0