HTTP: Add client and server

[nokome]

See previous implementations:

• https://github.com/stencila/schema/blob/0a731f60ce2736947f68c200d430258d3339d73a/js/src/comms/HttpClient.ts
• https://github.com/stencila/schema/blob/0a731f60ce2736947f68c200d430258d3339d73a/js/src/comms/HttpServer.ts

[stencila-ci]

🎉 This issue has been resolved in version 1.0.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀