Support for Before/After Hooks

[blad]

Add support for before and after hooks, to modify the request or response objects.

new Mockingjays().start({
  // ...  usual options
  before: request => {
    {body, qa, host, path, headers} = request
    // .. modify request before it is processed by Mockingjays
    return {body, qa, host, path, headers}
  },


  after: response => {
    // modify response object.
    response.code = 200
    response.data = {...}
    return response
  }
});