title: superagent doesn't return set-cookie header
body: <p>I am using superagent to POST login data to my external endpoint (at a different origin). This external endpoint returns a JWT, as well as a set-header cookie with the JWT inside it as well. I use this cookie to render pages server-side if a user is already logged in.</p>
  
  <p>However, when I check </p>
  
  <pre><code>request.end((err, res) =&gt; {
    console.log(res)
  }
  </code></pre>
  
  <p>I do not see any set-header cookie. What am I doing wrong? If it helps, I am using <a href="https://github.com/erikras/react-redux-universal-hot-example" rel="nofollow noreferrer">this boilerplate's</a> ApiClient.js.</p>