title: How can I pass parameters through an OAuth authentication so that my callback or controller can use?
body: <p>I am using OAuth to a provider (LinkedIn).</p>
  
  <p>I want to be able to pass parameters so that when someone signs-up, I can add some additional values at the time the new User is created (I am using Devise).</p>
  
  <p>But how do I do that?</p>
  
  <p>It looks like the link goes to the provider, which then makes a callback to my application.  How can I pass parameters from that link?</p>