title: Jenkins "Trigger builds remotely" > "Authentication Token" option missing
body: <p>I have just been working on setting up Jenkins (latest - 2.5) behind a reverse proxy with Nginx so that I can access it over HTTPS.</p>
  
  <p>It's working, however my Multibranch Pipeline jobs no longer have the "Trigger Builds Remotely" option in the main config. I don't think I changed any other configurations. Any ideas what happened and how to get it back?</p>
  
  <p>Here's what I want back:</p>
  
  <p><a href="https://i.stack.imgur.com/0lMrz.png" rel="noreferrer"><img src="https://i.stack.imgur.com/0lMrz.png" alt="Screenshot of what I want back"></a></p>