Kubernetes: Windows nodes support

[MOZGIII]

See RFC for the context.

Kubernetes has support for Nodes running Windows and Windows Containers. It's an actual Windows OS running kubelet, not the Kubernetes running in the Linux VM under "Docker for Windows" (that should already work fine).

The main problem with supporting Windows is not the implementation - it's just a few changes that are very easy to grasp - but the ability to test the quality continuously after we claim we support it. So, pretty much, we need a way to run E2E tests on a Windows cluster within our CI system.

The easiest way to get such a cluster is to use a managed cloud on Azure. The good thing is it's probably what our users would use in the first place.

However, it's not obvious if this is a highly demanded feature.

If you're reading this and you need Vector for Windows nodes - add your :+1: to this issue!

Refs:

• https://kubernetes.io/docs/setup/production-environment/windows/intro-windows-in-kubernetes/
• https://github.com/Microsoft/hcsshim/tree/master/cmd/runhcs

[Hoverbear]

(Side note, if you're using Vector with windows, do please let us know and let us know if we can improve support! See also #2719 )

[gattytto]

yes it is demanded, it would also be nice to have a headless shim-only windows node for the runhcs so to have less complexity on the windows node.