Initial version of Flannel using CNI (#1486)

* Updates Controller Manager/Kubelet with Flannel's required configuration for CNI
* Removes old Flannel installation
* Install CNI enabled Flannel DaemonSet/ConfigMap/CNI bins and config (with portmap plugin) on host
* Uses RBAC if enabled
* Fixed an issue that could occur if br_netfilter is not a module and net.bridge.bridge-nf-call-iptables sysctl was not set

roles/kubernetes-apps/network_plugin/flannel/tasks/main.yml

@@ -0,0 +1,22 @@
+---
+- name: "Flannel | Create ServiceAccount ClusterRole and ClusterRoleBinding"
+  command: "{{ bin_dir }}/kubectl apply -f {{ kube_config_dir }}/cni-flannel-rbac.yml"
+  run_once: true
+  when: rbac_enabled and flannel_rbac_manifest.changed
+
+- name: Flannel | Start Resources
+  kube:
+    name: "kube-flannel"
+    kubectl: "{{ bin_dir }}/kubectl"
+    filename: "{{ kube_config_dir }}/cni-flannel.yml"
+    resource: "ds"
+    namespace: "{{system_namespace}}"
+    state: "{{ item | ternary('latest','present') }}"
+  with_items: "{{ flannel_manifest.changed }}"
+  when: inventory_hostname == groups['kube-master'][0]
+
+- name: Flannel | Wait for flannel subnet.env file presence
+  wait_for:
+    path: /run/flannel/subnet.env
+    delay: 5
+    timeout: 600

roles/kubernetes-apps/network_plugin/meta/main.yml

@@ -3,6 +3,9 @@ dependencies:
   - role: kubernetes-apps/network_plugin/canal
     when: kube_network_plugin == 'canal'
     tags: canal
+  - role: kubernetes-apps/network_plugin/flannel
+    when: kube_network_plugin == 'flannel'
+    tags: flannel
   - role: kubernetes-apps/network_plugin/weave
     when: kube_network_plugin == 'weave'
     tags: weave