Istio Enable by default

[chrislovecnm]

Do we want istio enabled by default? @bgeesaman @wripley ???

[wripley]

We have it enabled by default in the holistic demo, but if you're asking about if we should enable it in the examples folder here, then I think it's fine if it is not. Thoughts @bgeesaman?

[bgeesaman]

I’m inclined to leave it as-is (not enabled by default) and just have well documented examples for it. It adds a lot of workloads and makes clusters immediately auto scale unless there are 6+ small nodes, so there’s a cost factor for running it without a specific need.