When kube-router is used as cni, rules might be added to the mangle table
to support external IPs. Therefore, mangle table should be flushed during
reset as well.
When using cluster.yml or scale.yml to add/scale nodes in the existing
k8s cluster, the `kubeadm init` wouldn't run. As a result, kube-proxy
wouldn't be created, and therefore the kube-proxy deletion task would
fail, e.g. in the case where kube-router is used and "kube_proxy_remove"
is set to true. As a workaround, add ignore_errors to the kube-proxy
deletion task.
This allows to easily override the gcr, quay, and docker repos with the
mirror repos in countries like China, where the default accesses are
blocked or unstable.
Qingkun Li