Add Kyverno policy to restrict ingresses to NYU by default
Unless an annotation hpc.nyu.edu/access=public
is set on an Ingress, it will autoamtically get a whitelist to only allow access from within NYU.
Fixes kubernetes-bare-metal#66
Should probably be rolled out in two stages: first, accept the annotation (and check it). Only later will we apply the whitelist if it is not present.
Unfortunately Kyverno can't show a warning so we can't inform users directly this way.