Cannot control deployment of sub charts in error avoiding patterns

[edwbuck]

When deploying in a tiered deployment, it is not possible to have a single control variable that then enables and disables arbitrary collections of sub-charts. Each sub-chart must be enabled or disabled individually, permitting a person to make mistakes like "child clusters lack a upstream agent".

We need a system where we can turn on and off entire sets of sub-charts, or to pull the sub-charts upward such that they can be controlled from single flags preventing misconfiguration by relying on the user to set "these three items as enabled" without missing one, or setting the wrong one on.