kubeadm support (#1631)

* 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

roles/download/defaults/main.yml

@@ -19,6 +19,7 @@ download_always_pull: False
 
 # Versions
 kube_version: v1.7.3
+kubeadm_version: "{{ kube_version }}"
 etcd_version: v3.2.4
 # TODO(mattymo): Move calico versions to roles/network_plugins/calico/defaults
 # after migration to container download
@@ -31,11 +32,13 @@ flannel_version: "v0.8.0"
 flannel_cni_version: "v0.2.0"
 pod_infra_version: 3.0
 
-# Download URL's
+# Download URLs
 etcd_download_url: "https://storage.googleapis.com/kargo/{{etcd_version}}_etcd"
+kubeadm_download_url: "https://storage.googleapis.com/kubernetes-release/release/{{ kubeadm_version }}/bin/linux/amd64/kubeadm"
 
 # Checksums
 etcd_checksum: "274c46a7f8d26f7ae99d6880610f54933cbcf7f3beafa19236c52eb5df8c7a0b"
+kubeadm_checksum: "378e6052f8b178f8e6a38e8637681c72d389443b66b78b51b8ddc9a162c655c3"
 
 # Containers
 # Possible values: host, docker
@@ -132,6 +135,15 @@ downloads:
     container: "{{ etcd_deployment_type in [ 'docker', 'rkt' ] }}"
     repo: "{{ etcd_image_repo }}"
     tag: "{{ etcd_image_tag }}"
+  kubeadm:
+    version: "{{ kubeadm_version }}"
+    dest: "kubeadm"
+    sha256: "{{ kubeadm_checksum }}"
+    source_url: "{{ kubeadm_download_url }}"
+    url: "{{ kubeadm_download_url }}"
+    unarchive: false
+    owner: "root"
+    mode: "0755"
   hyperkube:
     container: true
     repo: "{{ hyperkube_image_repo }}"