Add etcd-events cluster for kube-apiserver

import_tasks will consume far less memory, so it should be
used whenever it is compatible.

* kubeadm support

* move k8s master to a subtask
* disable k8s secrets when using kubeadm
* fix etcd cert serial var
* move simple auth users to master role
* make a kubeadm-specific env file for kubelet
* add non-ha CI job

* change ci boolean vars to json format

* fixup

* Update create-gce.yml

* Update create-gce.yml

* Update create-gce.yml

* Added update CA trust step for etcd and kube/secrets roles

* Added load_balancer_domain_name to certificate alt names if defined. Reset CA's in RedHat os.

* Rename kube-cluster-ca.crt to vault-ca.crt, we need separated CA`s for vault, etcd and kube.

* Vault role refactoring, remove optional cert vault auth because not not used and worked. Create separate CA`s fro vault and etcd.

* Fixed different certificates set for vault cert_managment

* Update doc/vault.md

* Fixed condition create vault CA, wrong group

* Fixed missing etcd_cert_path mount for rkt deployment type. Distribute vault roles for all vault hosts

* Removed wrong when condition in create etcd role vault tasks.

Fixed sync_tokens fact
Fixed sync_certs for k8s tokens fact
Disabled register docker images changability
Fixed CNI dir permission
Fix idempotency for etcd pre upgrade checks

Now etcd role can optionally disable etcd cluster setup for faster
deployment when it is combined with etcd role.

Migrate older inline= syntax to pure yml syntax for module args as to be consistant with most of the rest of the tasks
Cleanup some spacing in various files
Rename some files named yaml to yml for consistancy

* 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>

systemctl daemon-reload should be run before when task modifies/creates
union for etcd. Otherwise etcd won't be able to start

Closes #892

Signed-off-by: Sergii Golovatiuk <sgolovatiuk@mirantis.com>

Includes hooks for triggering calico, kubelet, and kube-apiserver restarts
if etcd certs changed.

Add tags to allow more granular tasks filtering.
Add generator script for MD formatted tags found.
Add docs for tags how-to.

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

Improved docker reload command to wait for etcd to be
up before proceeding. Switched reload to run restart
because it can't reload if it is not guaranteed to be
in running state.

Move set_facts to the preinstall scope, so every role
may see it. For example, network plugins to see the etcd_endpoint.

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

* Enforce a etcd-proxy role to a k8s-cluster group members. This
provides an HA layout for all of the k8s cluster internal clients.
* Proxies to be run on each node in the group as a separate etcd
instances with a readwrite proxy mode and listen the given endpoint,
which is either the access_ip:2379 or the localhost:2379.
* A notion for the 'kube_etcd_multiaccess' is: ignore endpoints and
loadbalancers and use the etcd members IPs as a comma-separated
list. Otherwise, clients shall use the local endpoint provided by a
etcd-proxy instances on each etcd node. A Netwroking plugins always
use that access mode.
* Fix apiserver's etcd servers args to use the etcd_access_endpoint.
* Fix networking plugins flannel/calico to use the etcd_endpoint.
* Fix name env var for non masters to be set as well.
* Fix etcd_client_url was not used anywhere and other etcd_* facts
evaluation was duplicated in a few places.
* Define proxy modes only in the env file, if not a master. Del
an automatic proxy mode decisions for etcd nodes in init/unit scripts.
* Use Wants= instead of Requires= as "This is the recommended way to
hook start-up of one unit to the start-up of another unit"
* Make apiserver/calico Wants= etcd-proxy to keep it always up

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>
Co-authored-by: Matthew Mosesohn <mmosesohn@mirantis.com>

Running etcd in Docker reduces the number of individual file
downloads and services running on the host.

Note: etcd container v3.0.1 moves bindir to /usr/local/bin

Fixes: #298

* Set ETCD_INITIAL_CLUSTER_STATE from `new` to `existing`,
because parameter `new` makes sense only on cluster assembly
stage.
* If cluster exists and current node is not a part
of the cluster, add it with command `etcdctl add member name url`.

Closes kubespray/kargo/#270

fix etcd configuration for nodes

fix wrong calico checksums

using a var name etcd_bin_dir

fix etcd handlers for sysvinit

using a var name etcd_bin_dir

sysvinit script

review etcd configuration