Currently auth_token middleware does not concern identity endpoint
update since service catalog is not updated after service having
auth_token middleware started.
Add invalidation logic when EndpointNotfound exception occurs so
that auth_token middleware can be notified of sevice catalog update
without restart.
Change-Id: I631ee1538883d732fe3987b172d987f703dad5c0
Closes-Bug: #1813739
Lance Bragstad