[jjo] add kube-router support (#3339)

* [jjo] add kube-router support

Fixes cloudnativelabs/kube-router#147.

* add kube-router as another network_plugin choice
* support most used kube-router flags via
  `kube_router_foo` vars as other plugins
* implement replacing kube-proxy (--run-service-proxy=true) via
  `kube_proxy_mode: none`, verified in a _non kubeadm_enabled_
  install, should also work for recent kubeadm releases via
  `skipKubeProxyInstall: true` config

* [jjo] address PR#3339 review from @woopstar

* add busybox image used by kube-router to downloads

* fix busybox download groups key

* rework kubeadm_enabled + kube_router_run_service_proxy

- verify it working ok w/the kubeadm_enabled and
  kube_router_run_service_proxy true or false

- introduce `kube_proxy_remove` fact, to decouple logic
  from kube_proxy_mode (which affects kubeadm configmap
  settings, thus no-good to ab-use it to 'none')

* improve kube-router.md re: kubeadm_enabled and kube_router_run_service_proxy

* address @woopstar latest review

* add inventory/sample/group_vars/k8s-cluster/k8s-net-kube-router.yml

* fix kube_router_run_service_proxy conditional for kube-proxy removal

* fix kube_proxy_remove fact (w/ |bool), add some needed kube-proxy tags on my and existing changes

* update kube-router tolerations for 1.12 compatibility

* add PriorityClass to kube-router DaemonSet

.gitlab-ci.yml

@@ -296,10 +296,18 @@ before_script:
 # stage: deploy-special
   MOVED_TO_GROUP_VARS: "true"
 
+.centos7_kube_router_variables: &centos7_kube_router_variables
+# stage: deploy-special
+  MOVED_TO_GROUP_VARS: "true"
+
 .coreos_alpha_weave_ha_variables: &coreos_alpha_weave_ha_variables
 # stage: deploy-special
   MOVED_TO_GROUP_VARS: "true"
 
+.coreos_kube_router_variables: &coreos_kube_router_variables
+# stage: deploy-special
+  MOVED_TO_GROUP_VARS: "true"
+
 .ubuntu_rkt_sep_variables: &ubuntu_rkt_sep_variables
 # stage: deploy-part1
   MOVED_TO_GROUP_VARS: "true"
@@ -316,6 +324,10 @@ before_script:
 # stage: deploy-special
   MOVED_TO_GROUP_VARS: "true"
 
+.ubuntu_kube_router_variables: &ubuntu_kube_router_variables
+# stage: deploy-special
+  MOVED_TO_GROUP_VARS: "true"
+
 .opensuse_canal_variables: &opensuse_canal_variables
 # stage: deploy-part2
   MOVED_TO_GROUP_VARS: "true"
@@ -615,6 +627,17 @@ gce_centos7-calico-ha-triggers:
   when: on_success
   only: ['triggers']
 
+gce_centos7-kube-router:
+  stage: deploy-special
+  <<: *job
+  <<: *gce
+  variables:
+    <<: *gce_variables
+    <<: *centos7_kube_router_variables
+  when: manual
+  except: ['triggers']
+  only: ['master', /^pr-.*$/]
+
 gce_opensuse-canal:
   stage: deploy-part2
   <<: *job
@@ -638,6 +661,17 @@ gce_coreos-alpha-weave-ha:
   except: ['triggers']
   only: ['master', /^pr-.*$/]
 
+gce_coreos-kube-router:
+  stage: deploy-special
+  <<: *job
+  <<: *gce
+  variables:
+    <<: *gce_variables
+    <<: *coreos_kube_router_variables
+  when: manual
+  except: ['triggers']
+  only: ['master', /^pr-.*$/]
+
 gce_ubuntu-rkt-sep:
   stage: deploy-part2
   <<: *job
@@ -682,6 +716,17 @@ gce_ubuntu-flannel-sep:
   except: ['triggers']
   only: ['master', /^pr-.*$/]
 
+gce_ubuntu-kube-router-sep:
+  stage: deploy-special
+  <<: *job
+  <<: *gce
+  variables:
+    <<: *gce_variables
+    <<: *ubuntu_kube_router_variables
+  when: manual
+  except: ['triggers']
+  only: ['master', /^pr-.*$/]
+
 # Premoderated with manual actions
 ci-authorized:
   <<: *job