Automatic merge from submit-queue (batch tested with PRs 49916, 50050) Update images used in the node e2e benchmark tests Ref: https://github.com/kubernetes/kubernetes/issues/42926 - Update the cosbeta image since the new version contains a 'du' command fix that affects Docker performance. - Add the coreos and ubuntu image that run Docker 1.12.6 so that we will have more data to compare. **Release note**: ``` None ```