title: MVC5 Claims version of the Authorize attribute
body: <p>I'm trying out some of the new stuff in VS2013 RC with MVC5 and the new OWIN authentication middleware.</p>
  
  <p>So, I'm used to using the <code>[Authorize]</code> attribute to limit actions by role but I'm trying to use claims/activity based authorization, and I can't find an equivalent attribute for it.</p>
  
  <p>Is there an obvious one I'm missing or do I need to roll my own? I kinda expected there to be one out of the box.</p>
  
  <p>What I'm looking for specifically is something along the lines of <code>[Authorize("ClaimType","ClaimValue")]</code> I suppose.</p>
  
  <p>Thanks in advance.</p>