cluster/kube: deploy admitomatic webhook

This has been (succesfully) tested on prod and then rolled back.

Change-Id: I22657f66b4aeaa8a0ae452035ba18a79f4549b14
diff --git a/cluster/kube/k0-admitomatic.jsonnet b/cluster/kube/k0-admitomatic.jsonnet
new file mode 100644
index 0000000..efff661
--- /dev/null
+++ b/cluster/kube/k0-admitomatic.jsonnet
@@ -0,0 +1,7 @@
+// Only the admitomatic instance in k0.
+
+local k0 = (import "k0.libsonnet").k0;
+
+{
+    admitomatic: k0.admitomatic,
+}