Label support for Update handler

Signed-off-by: Alex Ellis <alexellis2@gmail.com>

gateway/handlers/createhandler.go

@@ -75,7 +75,7 @@ func makeSpec(request *requests.CreateFunctionRequest, maxRestarts uint64, resta
 	}
 	labels := map[string]string{"function": "true"}
 	if request.Labels != nil {
-		for k, v := range request.Labels {
+		for k, v := range *request.Labels {
 			labels[k] = v
 		}
 	}

gateway/handlers/update_handler.go

@@ -93,6 +93,13 @@ func updateSpec(request *requests.CreateFunctionRequest, spec *swarm.ServiceSpec
 		"function": "true",
 		"uid":      fmt.Sprintf("%d", time.Now().Nanosecond()),
 	}
+
+	if request.Labels != nil {
+		for k, v := range *request.Labels {
+			spec.TaskTemplate.ContainerSpec.Labels[k] = v
+		}
+	}
+
 	spec.TaskTemplate.Networks = nets
 	spec.TaskTemplate.Placement = &swarm.Placement{
 		Constraints: constraints,