Rework inventory all by real groups' vars

* Leave all.yml to keep only optional vars
* Store groups' specific vars by existing group names
* Fix optional vars casted as mandatory (add default())
* Fix missing defaults for an optional IP var
* Relink group_vars for terraform to reflect changes

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

roles/kubernetes/preinstall/defaults/main.yml

@@ -17,6 +17,8 @@ common_required_pkgs:
 # GCE docker repository
 disable_ipv6_dns: false
 
+kube_cert_group: kube-cert
+kube_config_dir: /etc/kubernetes
 
 # For the openstack integration kubelet will need credentials to access
 # openstack apis like nova and cinder. Per default this values will be
@@ -27,9 +29,6 @@ openstack_password: "{{ lookup('env','OS_PASSWORD')  }}"
 openstack_region: "{{ lookup('env','OS_REGION_NAME')  }}"
 openstack_tenant_id: "{{ lookup('env','OS_TENANT_ID')|default(lookup('env','OS_PROJECT_ID'),true)  }}"
 
-# All clients access each node individually, instead of using a load balancer.
-etcd_multiaccess: true
-
 # Container Linux by CoreOS cloud init config file to define /etc/resolv.conf content
 # for hostnet pods and infra needs
 resolveconf_cloud_init_conf: /etc/resolveconf_cloud_init.conf