Add authorization for RESTful API

[huan]

need to be integrated with gRPC

Links

• Swagger Bearer Authentication https://swagger.io/docs/specification/authentication/bearer-authentication/
• Postman Learning Center: Authorizing requests https://learning.postman.com/docs/sending-requests/authorization/
• https://developer.mozilla.org/en-US/docs/Web/HTTP/Authentication

[huan]

The Wechaty gRPC is using the following schema for authorization:

Authorization: Wechaty ${TOKEN}

We will follow this authorization schema as the HTTP header of OpenAPI.