Revert "Use K8s 1.14 and add kubeadm experimental control plane mode (#4317)" (#4510)

This reverts commit 316508626d.

roles/kubernetes/master/defaults/main/main.yml

@@ -23,18 +23,11 @@ kube_apiserver_storage_backend: etcd3
 # By default, force back to etcd2. Set to true to force etcd3 (experimental!)
 force_etcd3: false
 
-kube_etcd_cacert_file: ca.pem
-kube_etcd_cert_file: node-{{ inventory_hostname }}.pem
-kube_etcd_key_file: node-{{ inventory_hostname }}-key.pem
-
 # Associated interfaces must be reachable by the rest of the cluster, and by
 # CLI/web clients.
 kube_controller_manager_bind_address: 0.0.0.0
 kube_scheduler_bind_address: 0.0.0.0
 
-# discovery_timeout modifies the discovery timeout
-discovery_timeout: 5m0s
-
 # audit support
 kubernetes_audit: false
 # path to audit log file
@@ -85,6 +78,7 @@ kube_apiserver_request_timeout: "1m0s"
 
 # 1.9 and below Admission control plug-ins
 kube_apiserver_admission_control:
+  - Initializers
   - NamespaceLifecycle
   - LimitRanger
   - ServiceAccount
@@ -105,7 +99,8 @@ kube_apiserver_enable_admission_plugins: []
 kube_apiserver_disable_admission_plugins: []
 
 # extra runtime config
-kube_api_runtime_config: []
+kube_api_runtime_config:
+  - admissionregistration.k8s.io/v1alpha1
 
 ## Enable/Disable Kube API Server Authentication Methods
 kube_basic_auth: false