Migrate API docs to new platform

[ogarrett]

API documentation:

https://github.com/deepfence/deepfence_runtime_api
https://deepfence.github.io/deepfence_runtime_api/ (edited)

We use swagger to generate .rst file / .html file
https://github.com/deepfence/deepfence_docs/blob/0c448525c6cbd83067dd642ac1abf9eb8a843471/api.rst
https://github.com/deepfence/deepfence_runtime_api/blob/master/index.html

Currently, the new docs point to the github repo for the API docs: https://.../threatstryker/api-reference so there’s no rush to move the API docs into the new platform.