Update CHANGELOG and README to reflect v12.0.0 and v12.0.1#1308

Merged

k8s-ci-robot merged 1 commit intokubernetes-client:masterfrom

palnabarun:update-changelog

Nov 13, 2020

Commits on Nov 7, 2020

Update CHANGELOG and README to reflect v12.0.0 and v12.0.1
palnabarun
committed