Fix Some Typos in kubernetes master role (#1547)

* Fix Typo etc3 -> etcd3

* Fix typo in post-upgrade of master. stop -> start

roles/kubernetes/master/tasks/post-upgrade.yml

@@ -13,7 +13,7 @@
     seconds: 10
   when: needs_etcd_migration|bool
 
-- name: "Post-upgrade | stop kubelet on all masters"
+- name: "Post-upgrade | start kubelet on all masters"
   service:
     name: kubelet
     state: started

roles/kubernetes/master/tasks/pre-upgrade.yml

@@ -42,7 +42,7 @@
   when: kube_apiserver_storage_backend == "etcd3"
   failed_when: false
 
-- name: "Pre-upgrade | etcd3 upgrade | use etcd2 unless forced to etc3"
+- name: "Pre-upgrade | etcd3 upgrade | use etcd2 unless forced to etcd3"
   set_fact:
     kube_apiserver_storage_backend: "etcd2"
   when: old_data_exists.rc == 0 and not force_etcd3|bool