Moves setup files into embedded package.

internal/setup/cluster-services/coredns/kustomize.template/coredns-custom-config.yaml

@@ -0,0 +1,28 @@
+---
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  name: coredns-custom
+  namespace: kube-system
+data:
+  # Custom server block for internal domains. All internal domains should
+  # resolve to the cluster proxy.
+  internal.server: |
+    {{ .cloud.internalDomain }} {
+      errors
+      cache 30
+      reload
+      template IN A {
+        match (.*)\.{{ .cloud.internalDomain | strings.ReplaceAll "." "\\." }}\.
+        answer "{{`{{ .Name }}`}} 60 IN A {{ .cluster.loadBalancerIp }}"
+      }
+      template IN AAAA {
+        match (.*)\.{{ .cloud.internalDomain | strings.ReplaceAll "." "\\." }}\.
+        rcode NXDOMAIN
+      }
+    }
+  # Custom override to set external resolvers.
+  external.override: |
+    forward . {{ .cloud.dns.externalResolver }} {
+      max_concurrent 1000
+    }