* Apply linux node selector to coreDNS deployment

* Remove comment before linux node selector on manifests

* mend

* 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

* 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

ensure there is pin priority for docker package to avoid upgrade of docker to incompatible version

remove empty when line

ensure there is pin priority for docker package to avoid upgrade of docker to incompatible version

force kubeadm upgrade due to failure without --force flag

ensure there is pin priority for docker package to avoid upgrade of docker to incompatible version

added nodeSelector to have compatibility with hybrid cluster with win nodes, also fix for download with missing container type

fixes in syntax and LF for newline in files

fix on yamllint check

ensure there is pin priority for docker package to avoid upgrade of docker to incompatible version

some cleanup for innecesary lines

remove conditions for nodeselector

Templates (even without actual templating inside) should have j2 extension but should not be rendered with j2 extension

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

* Add RBAC policies to dnsmasq

* fix merge conflict

* yamllint

* use .j2 extension for dnsmasq autoscaler

Added toleration to DNS, netchecker, fluentd, canal, and
calico policy.

Also small fixes to make yamllint pass.

* Adding yaml linter to ci check

* Minor linting fixes from yamllint

* Changing CI to install python pkgs from requirements.txt

- adding in a secondary requirements.txt for tests
- moving yamllint to tests requirements

Allows config changes made by Ansible to restart dnsmasq deployment

By default kubedns and dnsmasq scale when installed.
Dnsmasq is no longer a daemonset. It is now a deployment.
Kubedns is no longer a replicationcluster. It is now a deployment.
Minimum replicas is two (to enable rolling updates).

Reduced memory erquirements for dnsmasq and kubedns

When DNSMasq is configured to read its settings
from a folder ('-7' or '--conf-dir' option) it only
checks that the directory exists and doesn't fail if
it's empty. It could lead to a situation when DNSMasq
is running and handles requests, but not properly
configured, so some of queries can't be resolved.

* Drop linux capabilities for unprivileged containerized
  worlkoads Kargo configures for deployments.
* Configure required securityContext/user/group/groups for kube
  components' static manifests, etcd, calico-rr and k8s apps,
  like dnsmasq daemonset.
* Rework cloud-init (etcd) users creation for CoreOS.
* Fix nologin paths, adjust defaults for addusers role and ensure
  supplementary groups membership added for users.
* Add netplug user for network plugins (yet unused by privileged
  networking containers though).
* Grant the kube and netplug users read access for etcd certs via
  the etcd certs group.
* Grant group read access to kube certs via the kube cert group.
* Remove priveleged mode for calico-rr and run it under its uid/gid
  and supplementary etcd_cert group.
* Adjust docs.
* Align cpu/memory limits and dropped caps with added rkt support
  for control plane.

Signed-off-by: Bogdan Dobrelya <bogdando@mail.ru>

Also place in global vars and do not repeat the kube_*_config_dir
and kube_namespace vars for better code maintainability and UX.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>

* Add dns_replicas, dns_memory/cpu_limit/requests vars for
dns related apps.
* When kube_log_level=4, log dnsmasq queries as well.
* Add log level control for skydns (part of kubedns app).
* Add limits/requests vars for dnsmasq (part of kubedns app) and
  dnsmasq daemon set.
* Drop string defaults for kube_log_level as it is int and
  is defined in the global vars as well.
* Add docs

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>

According to http://kubernetes.io/docs/user-guide/images/

 :
By default, the kubelet will try to pull each image from the
specified registry. However, if the imagePullPolicy property
of the container is set to IfNotPresent or Never, then a local\
image is used (preferentially or exclusively, respectively).

Use IfNotPresent value to allow images prepared by the download
role dependencies to be effectively used by kubelet without pull
errors resulting apps to stay blocked in PullBackOff/Error state
even when there are images on the localhost exist.

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>

Signed-off-by: Chad Swenson <chadswen@gmail.com>

Change additional dnsmasq opts:
- Adjust caching size and TTL
- Disable resolve conf to not create loops
- Change dnsPolicy to default (similarly to kubedns's dnsmasq). The
  ClusterFirst should not be used to not create loops
- Disable negative NXDOMAIN replies to be cached
- Make its very installation as optional step (enabled by default).
  If you don't want more than 3 DNS servers, including 1 for K8s, disable
  it.
- Add docs and a drawing to clarify DNS setup.
- Fix stdout logs for dnsmasq/kubedns app configs
- Add missed notifies to resolvconf -u handler
- Fix idempotency of resolvconf head file changes

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>