Release v0.4.2

Same as release v0.4.0, changes are:

• Fixed manifests so that the git tag and image from manifests is the same.
• Changed so that manifests now install in default namespace instead of nats-io

Image:

docker run synadia/nats-streaming-operator:0.4.2

To install:

kubectl apply -f https://github.com/nats-io/nats-streaming-operator/releases/download/v0.4.2/default-rbac.yaml
kubectl apply -f https://github.com/nats-io/nats-streaming-operator/releases/download/v0.4.2/deployment.yaml