title: Redis mark key volatile infinite expiration
body: <p>I want to mark keys as volatile but I dont want redis to expire them unless I hit a max memory configuration.</p>
  
  <p>Is it possible to mark a key as volatile but do so with an infinite value?</p>
  
  <p><strong>edit</strong></p>
  
  <p>I searched the googles and the mailing list and am not finding anything</p>