Add namespace to rbac-namespace-default

[StevenACoffman]

We suggest you apply -f manifests in the following order:

You choice of storage classes from ./configure
./rbac-namespace-default
./zookeeper
./kafka

If you add a copy of the 00namespace.yml to the rbac-namespace-default folder, then you can successfully run them in the recommended order.

Sorry I'm not submitting a pull request, but I'm only using my phone at present, and without a laptop it's a bit more tricky than submitting an issue.

[solsson]

Safe to do directly in master :)