Built-in resolver to call Rest API

[daniel-duarte]

Provide a built-in resolver to call a rest API.

[danielduarte]

Provided as Flowed plugins:

• flowed-openapi An OpenApi resolver
• flowed-http A generic HTTP/S resolver

Usage (example in TypeScript):

import { FlowedPlugin } from 'flowed';
import FlowedOpenApi from 'flowed-openapi';

FlowManager.installPlugin(FlowedOpenApi as FlowedPlugin);

// All set to use the resolver name "flowed::OpenApi"!

It is pretty similar to integrate flowed-http.

Note that this solution is not included as a part of the package flowed to preserve it as light as possible for those that does not need the HTTP feature. But as shown above, it is super easy to install and use.