Fix broken trust-scoped token example

Change-Id: I7133d4c4029d059a3d921bbd50f2700b6bf22f32
Merge "Fix broken trust-scoped token example"
Fix /v3/auth/token -> /v3/auth/tokens (bug 1145267)

Change-Id: I901aaf03b68cb1e00fbe6722e564b235c5a4bf32