I found a potential use case where `writable` could be null and therfore
not treated like a boolean, so this adds an extra default statement to
avoid negating a non-boolean as boolean which would lead to undefined. refs #4020

--address deprecated

In v1beta1 of `ClusterConfiguration` the extraVolumes `writable` field was changed to `readOnly` and its boolean value must be negated.

Also, the json field for `useHyperKubeImage` was incorrectly capitalized.

* allows to override the bind addresses for controller-manager and scheduler

Useful for Prometheus metrics monitoring

* Add bind addr override support in kubeadm/v1beta1

Adds support for override of bind addresses for controller-manager
and scheduler in kubeadm/v1beta1

* Move location of bind address vars

* Remove double declaration of schedulerExtraArgs

* Use master node taint same as kubeadm configuration v1alpha3 or before.

- Creates and defaults an ansible variable for every configuration option in the `kubeproxy.config.k8s.io/v1alpha1` type spec
  - Fixes vars that were orphaned by removing non-kubeadm
  - Fixes previously harcoded kubeadm values
- Introduces a `main` directory for role default files per component (requires ansible 2.6.0+)
  - Split out just `kube-proxy.yml` in this first effort
- Removes the kube-proxy server field patch task

We should continue to pull out other components from `main.yml` into their own defaults files as I did here for `defaults/main/kube-proxy.yml`. I hope for and will need others to join me in this refactoring across the project until each component config template has a matching role defaults file, with shared defaults in `kubespray-defaults` or `downloads`

Webhook token auth:
https://kubernetes.io/docs/reference/access-authn-authz/authentication/#webhook-token-authentication

Fixes #3063.

* controlPlaneEndpoint set up through load balancer should be possible  even in single master setups

Enable load balancer for single-master setups
Fixes an issue where single-master setups are not reachable using the usual admin.conf from outside the cluster. 

controlPlaneEndpoint set up through load balancer should be possible  even in single master setups

* add fix to other api versions

* remove obsolete check completely

* remove check, pass 2

* removes checks in client configuration

* delete 'and'

* Streamline path to certs dir

* More fixes

* Set path to etcd certs in kubernetes defaults instead

* Upgrade kubernetes to v1.13.0

* Remove all precense of scheduler.alpha.kubernetes.io/critical-pod in templates

* Fix cert dir

* Use kubespray v2.8 as baseline for gitlab

* Remove non-kubeadm deployment

* More cleanup

* More cleanup

* More cleanup

* More cleanup

* Fix gitlab

* Try stop gce first before absent to make the delete process work

* More cleanup

* Fix bug with checking if kubeadm has already run

* Fix bug with checking if kubeadm has already run

* More fixes

* Fix test

* fix

* Fix gitlab checkout untill kubespray 2.8 is on quay

* Fixed

* Add upgrade path from non-kubeadm to kubeadm. Revert ssl path

* Readd secret checking

* Do gitlab checks from v2.7.0 test upgrade path to 2.8.0

* fix typo

* Fix CI jobs to kubeadm again. Fix broken hyperkube path

* Fix gitlab

* Fix rotate tokens

* More fixes

* More fixes

* Fix tokens

* Set configure-cloud-routes=false as default if no network plugin is used

As configure-cloud-routes default value is `true`, so it need to be set to `false` when not required to avoid error messages like:
"Couldn't reconcile node routes: error listing routes: unable to find route table for AWS cluster" 
on, for example, AWS installations that don't use cloud native routing.

* Update kube-controller-manager.manifest.j2

remove extra spaces

This takes care of a few arbitrary use cases that may require custom mounts
inside of apiserver, controller manager, or scheduler.

* Switch to kubeadm deployment mode

Discuss:https://github.com/kubernetes-incubator/kubespray/issues/3301

* Add non-kubeadm upgrage to kubeadm cluster

* Add resource-container flag to kube-proxy manifest

* add resourceContainer: "" to kubeadm kube-proxy configs

* failed

* version_compare

* succeeded

* skipped

* success

* version_compare becomes version since ansible 2.5

* ansible minimal version updated in doc and spec

* last version_compare

* [jjo] add kube-router support

Fixes cloudnativelabs/kube-router#147.

* add kube-router as another network_plugin choice
* support most used kube-router flags via
  `kube_router_foo` vars as other plugins
* implement replacing kube-proxy (--run-service-proxy=true) via
  `kube_proxy_mode: none`, verified in a _non kubeadm_enabled_
  install, should also work for recent kubeadm releases via
  `skipKubeProxyInstall: true` config

* [jjo] address PR#3339 review from @woopstar

* add busybox image used by kube-router to downloads

* fix busybox download groups key

* rework kubeadm_enabled + kube_router_run_service_proxy

- verify it working ok w/the kubeadm_enabled and
  kube_router_run_service_proxy true or false

- introduce `kube_proxy_remove` fact, to decouple logic
  from kube_proxy_mode (which affects kubeadm configmap
  settings, thus no-good to ab-use it to 'none')

* improve kube-router.md re: kubeadm_enabled and kube_router_run_service_proxy

* address @woopstar latest review

* add inventory/sample/group_vars/k8s-cluster/k8s-net-kube-router.yml

* fix kube_router_run_service_proxy conditional for kube-proxy removal

* fix kube_proxy_remove fact (w/ |bool), add some needed kube-proxy tags on my and existing changes

* update kube-router tolerations for 1.12 compatibility

* add PriorityClass to kube-router DaemonSet

* Upgrade kubernetes to v1.12.0

Use kubeadm v1alpha3 config

* Upgrade coredns and etcd

* Upgrage docker to 18.06

* Better fix for openstack cinder zone issue[1][2]
using ignore-volume-az option[3].
[1]: https://github.com/kubernetes-incubator/kubespray/pull/2155
[2]: https://github.com/kubernetes-incubator/kubespray/pull/2346
[3]: https://github.com/kubernetes/kubernetes/pull/53523

* Remove kube-scheduler-policy.yaml

* Changes to assign pod priority to kube components.

* Removed the boolean flag pod_priority_assignment

* Created new priorityclass k8s-cluster-critical

* Created new priorityclass k8s-cluster-critical

* Fixed the trailing spaces

* Fixed the trailing spaces

* Added kube version check while creating Priority Class k8s-cluster-critical

* Moved k8s-cluster-critical.yml

* Moved k8s-cluster-critical.yml to kube_config_dir

* Support for AWS cloud-config

* Update docs

* Fix version incompatibilities

* Do not use shorthand `default`

* Add new cloud config variable, roleArn