title: Create same access token for multiple devices
body: <p>I am using the katana owin project in my Web Api 2 project.
  I want that user will be able to login from different devices,
  for example: smartphone and tablet.
  And that the user will get the same token if its not yet passed.
  In the current situation, if the user is login from his smartphone he will get one token and refresh token, and then if he login from his tablet he will get another token and a new refresh token.
  How can I solved this?</p>
  
  <p>Thanks!</p>