Make sure the auth middleware for tokan validation
Make sure the auth middleware for tokan validation

and getting auth headers from the token are intialized
once.

When initialized for each request, the in-memory cache or memcache
gets reset reuslting in lose of cached tokens and so for each request
middleware goes to identity server for token validation.

Change-Id: Ib34ca2e052f862d2d5a45210b3b566ed80ed8b5f
Closes-Bug: 1718491

rombie/contrail-controller,nischalsheth/contrail-controller,rombie/contrail-controller,nischalsheth/contrail-controller,rombie/contrail-controller,eonpatapon/contrail-controller,eonpatapon/contrail-controller,eonpatapon/contrail-controller,rombie/contrail-controller,nischalsheth/contrail-controller,nischalsheth/contrail-controller,eonpatapon/contrail-controller,eonpatapon/contrail-controller,nischalsheth/contrail-controller,eonpatapon/contrail-controller,rombie/contrail-controller,eonpatapon/contrail-controller,rombie/contrail-controller,nischalsheth/contrail-controller,rombie/contrail-controller,nischalsheth/contrail-controller,nischalsheth/contrail-controller