Vonage

- Remove the Number Insight v2 beta which was not in use and is going to be deprecated
- Lower the VerifyV2 minimum channel timeout to 15s

- Add support for the [Vonage Application API](https://developer.vonage.com/en/application/overview).
- Internal refactoring

- Add support for the [Vonage Number Insight API](https://developer.vonage.com/en/number-insight/overview).
- Update minimum dependency version

- Add support for the [Vonage Voice API](https://developer.vonage.com/en/voice/voice-api/overview).
- Add `http_client` property to each module that has an HTTP Client, e.g. Voice, Sms, Verify.

- Add support for the [Vonage Messages API](https://developer.vonage.com/en/messages/overview).

- Add support for the [Vonage Verify V2 API](https://developer.vonage.com/en/verify/overview).
- Expose error classes at the top level of the `vonage-http-client` package.