This fixes #3014

ingress-nginx 0.16.2 (https://github.com/kubernetes/ingress-nginx/releases/tag/nginx-0.16.2)

This patch simplify ingress-nginx deployment by default deploy on
master, with customizable options; on the other hand, remove the
additional Ansible group "kube-ingress" and its k8s node label
injection.

Reference to https://kubernetes.io/docs/concepts/services-networking/ingress/#prerequisites:

    GCE/Google Kubernetes Engine deploys an ingress controller on the master.

By changing `ingress_nginx_nodeselector` plus custom k8s node
label, user could customize the DaemonSet deployment target.

If `ingress_nginx_nodeselector` is empty, will deploy DaemonSet on
every k8s node.

* Add tags for cert serial tasks

This will help facilitate tag-based deployment of specific components.

* fixup kubernetes node

The number of pods on a given node is determined by the  --max-pods=k
directive. When the address space is exhausted, no more pods can be
scheduled even if from the --max-pods-perspective, the node still has
capacity.

The special case that a pod is scheduled and uses the node IP in the
host network namespace is too "soft" to derive a guarantee.

Comparing kubelet_max_pods with kube_network_node_prefix when given
allows to assert that pod limits match the CIDR address space.

* Upgrade k8s to 1.10.2

Bumped etcd version to 3.2.16 as recommended

* Add ipvs fix for v1.10

* change flannel addons test to ha

* Move front-proxy-client certs back to kube mount

We want the same CA for all k8s certs

* Refactor vault to use a third party module

The module adds idempotency and reduces some of the repetitive
logic in the vault role

Requires ansible-modules-hashivault on ansible node and hvac
on the vault hosts themselves

Add upgrade test scenario
Remove bootstrap-os tags from tasks

* fix upgrade issues

* improve unseal logic

* specify ca and fix etcd check

* Fix initialization check

bump machine size

* sysctl file should be in defaults so that it can be overriden

* Change sysctl_file_path to be consistent with roles/kubernetes/preinstall/defaults/main.yml

Changed from OS_PROJECT_ID to OS_PROJECT_NAME.

All checks test if this is defined meaning there is no way to undefine it.

Changed from OS_PROJECT_ID to OS_PROJECT_NAME.

While `do` looks cleaner, forcing this extra option in ansible.cfg
seems to be more invasive. It would be better to keep the traditional
approach of `set dummy = ` instead.

Kubernetes makes this namespace automatically, so there is
no need for kubespray to manage it.

This file should only be updated during kubelet upgrade so that
master components are not accidentally restarted first during
preinstall stage.

Labels from role (node-role.k8s.io/node) and labels from inventory are merged into node-labels parameter in kubelet

The ability to create dedicated node for ingress nginx controller
host type network for nginx controller

and add from example https://github.com/kubernetes/ingress-nginx/blob/master/docs/examples/static-ip/nginx-ingress-controller.yaml
terminationGracePeriodSeconds: 60

Added CoreDNS to downloads

Updated with labels. Should now work without RBAC too

Fix DNS settings on hosts

Rename CoreDNS service from kube-dns to coredns

Add rotate based on http://edgeofsanity.net/rant/2017/12/20/systemd-resolved-is-broken.html

Updated docs with CoreDNS info

Added labels and fixed minor settings from official yaml file: https://github.com/kubernetes/kubernetes/blob/release-1.9/cluster/addons/dns/coredns.yaml.sed

Added a secondary deployment and secondary service ip. This is to mitigate dns timeouts and create high resitency for failures. See discussion at 'https://github.com/coreos/coreos-kubernetes/issues/641#issuecomment-281174806'

Set dns list correct. Thanks to @whereismyjetpack

Only download KubeDNS or CoreDNS if selected

Move dns cleanup to its own file and import tasks based on dns mode

Fix install of KubeDNS when dnsmask_kubedns mode is selected

Add new dns option coredns_dual for dual stack deployment. Added variable to configure replicas deployed. Updated docs for dual stack deployment. Removed rotate option in resolv.conf.

Run DNS manifests for CoreDNS and KubeDNS

Set skydns servers on dual stack deployment

Use only one template for CoreDNS dual deployment

Set correct cluster ip for the dns server

1. 404 link url
2. kubelet_authentication_token_webhook is not work
3. kube_reserved variable set twice