Merge pull request #1060 from holser/etcdv3

Allow to specify etcd backend for kube-api

roles/kubernetes/master/defaults/main.yml

@@ -29,3 +29,4 @@ kube_apiserver_memory_limit: 2000M
 kube_apiserver_cpu_limit: 800m
 kube_apiserver_memory_requests: 256M
 kube_apiserver_cpu_requests: 300m
+kube_apiserver_storage_backend: etcd2

roles/kubernetes/master/templates/manifests/kube-apiserver.manifest.j2

@@ -41,6 +41,7 @@ spec:
     - --service-account-key-file={{ kube_cert_dir }}/apiserver-key.pem
     - --secure-port={{ kube_apiserver_port }}
     - --insecure-port={{ kube_apiserver_insecure_port }}
+    - --storage-backend={{ kube_apiserver_storage_backend }}
 {% if kube_api_runtime_config is defined %}
 {%   for conf in kube_api_runtime_config %}
     - --runtime-config={{ conf }}