
Automatic merge from submit-queue (batch tested with PRs 51845, 51868, 51864) Update sys spec to support docker 1.11-1.13 and overlay2. Fixes https://github.com/kubernetes/kubernetes/issues/32536. Update docker spec to: 1) Support overlay2; 2) Support docker version 1.11-1.13. @dchen1107 @yguo0905 @luxas /cc @kubernetes/sig-node-pr-reviews ```release-note Kubernetes 1.8 supports docker version 1.11.x, 1.12.x and 1.13.x. And also supports overlay2. ```