Remove kubedns and dnsmasq. Move dns_late phase after apps (#4406)

Both kubedns and dnsmasq modes are long not maintained.
We should run dns_late steps at the end because sshd
makes DNS lookups during Ansible run and has 2s timeouts
for each failed lookup trying to connect to coredns before
it is ready.

inventory/sample/group_vars/all/all.yml

@@ -35,7 +35,7 @@ nginx_kube_apiserver_healthcheck_port: 8081
 ## modules.
 # kubelet_load_modules: false
 
-## Upstream dns servers used by dnsmasq
+## Upstream dns servers
 # upstream_dns_servers:
 #   - 8.8.8.8
 #   - 8.8.4.4

inventory/sample/group_vars/k8s-cluster/k8s-cluster.yml

@@ -127,7 +127,7 @@ kube_encrypt_secret_data: false
 cluster_name: cluster.local
 # Subdomains of DNS domain to be resolved via /etc/resolv.conf for hostnet pods
 ndots: 2
-# Can be dnsmasq_kubedns, kubedns, coredns, coredns_dual, manual or none
+# Can be coredns, coredns_dual, manual or none
 dns_mode: coredns
 # Set manual server if using a custom cluster DNS server
 # manual_dns_server: 10.x.x.x
@@ -142,7 +142,6 @@ deploy_netchecker: false
 # Ip address of the kubernetes skydns service
 skydns_server: "{{ kube_service_addresses|ipaddr('net')|ipaddr(3)|ipaddr('address') }}"
 skydns_server_secondary: "{{ kube_service_addresses|ipaddr('net')|ipaddr(4)|ipaddr('address') }}"
-dnsmasq_dns_server: "{{ kube_service_addresses|ipaddr('net')|ipaddr(2)|ipaddr('address') }}"
 dns_domain: "{{ cluster_name }}"
 
 ## Container runtime
@@ -176,10 +175,6 @@ podsecuritypolicy_enabled: false
 # Download kubectl onto the host that runs Ansible in {{ bin_dir }}
 # kubectl_localhost: false
 
-# dnsmasq
-# dnsmasq_upstream_dns_servers:
-#   - /resolvethiszone.with/10.0.4.250
-#   - 8.8.8.8
 
 #  Enable creation of QoS cgroup hierarchy, if true top level QoS and pod cgroups are created. (default true)
 # kubelet_cgroups_per_qos: true