Prodaccess/Prodvider allow issuing short-lived certificates for all SSO
users to access the kubernetes cluster.
Currently, all users get a personal-$username namespace in which they
have adminitrative rights. Otherwise, they get no access.
In addition, we define a static CRB to allow some admins access to
everything. In the future, this will be more granular.
We also update relevant documentation.
Change-Id: Ia18594eea8a9e5efbb3e9a25a04a28bbd6a42153