title: Devstack: There was an error submitting the form. Please try again. (when launching instance)
body: <p><p>When i try to launch an instance on my devstack (kilo) from horizon dashboard i get a message "There was an error submitting the form. Please try again." </p>That problem exists only when i try to start instance from admin user(from demo user works well). Also I can make volume without errors. 
  I am working in ubuntu 14.04.<br>
  I think that the problem is in cinder, because of this error in log:</p>
  
  <blockquote>
    <p>Cinder</p>
    
    <blockquote>
      <p>ERROR cinder.api.middleware.fault [req-6eb7575e-aaf5-4884-ac3d-bfefb31f833d 28ad1bada6134e23b2b7ade80c745771 54b3a044c5824f269938c8d3c3d5e6b0] Caught error: Entity '(&lt;)class 'cinder.db.sqlalchemy.models.Snapshot'> has no property 'tenant_id'</p>
    </blockquote>
    
    <p>Horizon</p>
    
    <blockquote>
      <p>2015-06-29 08:14:12.535521   File "/usr/local/lib/python2.7/dist-packages/cinderclient/client.py", line 272, in request
      2015-06-29 08:14:12.535525     raise exceptions.from_response(resp, body)
      2015-06-29 08:14:12.535530 ClientException: The server has either erred or is incapable of performing the requested operation. (HTTP 500) (Request-ID: req-f98235a2-f894-4a07-9aa2-ef3c5aa7e9ef)</p>
    </blockquote>
  </blockquote>
  
  <p>Last week everything worked well.
  I tried reinstaling devstac, reinstaling ubuntu... so maybe someone know whats the problem??? :-/</p>