Provide a global config to change registry and org of all images

[viccuad]

Is your feature request related to a problem? Please describe.

Currently, if one wants to perform an airgap install for example, one needs to patch the chart by substituting the repository and org of all images.
Alternatively, one could change

image.org for the operator image
quarks-job.image.org for the quarks job image
operator.boshDNSDockerImage for the coredns image

But this is clunky and may get out of sync, as one needs to respect the tags.

Describe the solution you'd like

Provide a global config option to substitute all of them at the same time.

Describe alternatives you've considered

Additional context

This would be useful for testing and performing airgapped installs.

[cf-gitbot]

We have created an issue in Pivotal Tracker to manage this:

https://www.pivotaltracker.com/story/show/175611713

The labels on this github issue will be updated when the story is started.

[manno]

Like I said on slack, you should be able to use helm install .. --set global.image.pullPolicy to stop k8s from downloading the images and load the images manually into your registry.

If you decide to switch all images to another repo you will also need to switch quarks-secret and quarks-statefulset. I'd rather not make the helm templates any more complicated for now.