Add _saveCookies and jar

[ghost]

Can we add _saveCookies and jar to the agent? This will do the trick. Would be happy to submit a PR.

  out.agent = function () {
    var agent = supertest.agent.apply(null, arguments);
    var _agent = wrap(agent);
    _agent._saveCookies = agent._saveCookies;
    _agent.jar = agent.jar;
    return _agent;
  };

[benesch]

Good catch! Fixed another way, since it turns out we should just inherit from the agent prototype chain to expose all such properties, rather than special-casing the two you listed. Thanks for the report!

[benesch]

Released as v4.0.1. Cheers!