Log successful authorizations (with ttl)

server/http.go

@@ -299,6 +299,8 @@ func (h *Server) handleGrantTicket(w http.ResponseWriter, req *http.Request) {
 		return
 	}
 
+	log.Printf("authorized %s for %s (ttl=%ds)", username, service, int(ttl.Seconds()))
+
 	// Record the service in the session.
 	auth.AddService(service)