feat: add support for Kubernetes 1.16.4

[mboersma]

Reason for Change:
See https://github.com/kubernetes/kubernetes/blob/master/CHANGELOG-1.16.md#changelog-since-v1163

Issue Fixed:

Requirements:

• Windows artifacts uploaded to acsmirror blob store
• uses conventional commit messages
• includes documentation
• adds unit tests
• tested upgrade from previous version

Notes:
I'll collect the VHD-related changes into a separate PR so we can focus discussion on those changes.

[codecov]

Codecov Report

Merging #2436 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #2436   +/-   ##
=======================================
  Coverage   72.29%   72.29%           
=======================================
  Files         130      130           
  Lines       23603    23603           
=======================================
  Hits        17063    17063           
  Misses       5516     5516           
  Partials     1024     1024

[jackfrancis]

/lgtm

[acs-bot]

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