Move CI to use openfaas/* ns

This was a miss by refactoring work and is causing a CI failure

https://travis-ci.org/openfaas/faas/builds/404409816



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

contrib/ci.sh

@@ -4,7 +4,7 @@ docker swarm init --advertise-addr=127.0.0.1
 
 ./deploy_stack.sh --no-auth
 
-docker service update func_gateway --image=functions/gateway:latest-dev
+docker service update func_gateway --image=openfaas/gateway:latest-dev
 
 # Script makes sure OpenFaaS API gateway is ready before running tests