nginx-ingress: sync to upstream 0.30.0

Sync our chart to the upstream 0.30.0

Upstream has altered RBAC configuration:

RBAC is now enabled by default upstream. A single boolean enable rbac.create: true now exists, and controls creation of the Role and RoleBinding. Control of the ClusterRole creation based upon scope.enabled: false. There is no longer the need for rbac.createClusterRole: false. We set scope.enabled: true, so the ClusterRole is still not made by default.

The serviceAccount is now controlled by serviceAccount.create and serviceAccount.name. serviceAccount.create defaults to true

Upstream has provided defaults for HPA via controller.autoscaling:

Upstream has now uncommented the defaults for contoller.autoscaling to include integer values. It remains enabled: false at this time.

Remove semverCompare calls against chart image tags

Address #910 (closed) and remove semverCompare calls against that container image tags within this chart. This is a small change that can be rolled in with the rest of this update.

Closes #791 (closed)

Closes #910 (closed)