Keystone middleware doesn't like if token is unicode. It must be converted to string before validation.
Keystone middleware doesn't like if token is unicode. It must be converted
to string before validation.

Change-Id: I537f3ca96229fd9abef18d8ceb56f3fee6fd1296
Fixes-Bug: #1604773

codilime/contrail-controller,codilime/contrail-controller,codilime/contrail-controller,codilime/contrail-controller,codilime/contrail-controller,codilime/contrail-controller