support kubernete below kubernete v1.16

[huiwq1990]

What would you like to be added:

As upgrade CustomResourceDefinition solved with #1296 , kubefed could not deploy on kubernete v1.16 below.

Why is this needed:

We could not keep up with the newest k8s.

/kind feature

[makkes]

Thanks for raising this issue, @huiwq1990. However, Kubernetes 1.16 isn't supported by the community, anymore:

The Kubernetes project maintains release branches for the most recent three minor releases (1.20, 1.19, 1.18). Kubernetes 1.19 and newer receive approximately 1 year of patch support. Kubernetes 1.18 and older received approximately 9 months of patch support.

You will not receive patches for 1.16 by the community. I understand some vendors still support older versions but I'm not sure whether kubefed should support any Kubernetes version older than the three most recent minor revisions.

[huiwq1990]

Thanks, whether support not latest version really matter for me or someone else, any result please notify us.

[fejta-bot]

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[fejta-bot]

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