keepalived: Initial commit

Running `keepalived` as a DaemonSet will allow managing floating
"virtual" IP addresses for Kubernetes services with configured external
IP addresses.  The main services we want to expose outside the cluster
are _ingress-nginx_, Mosquitto, and RabbitMQ.  The `keepalived` cluster
will negotiate using the VRRF protocol to determine which node should
have each external address.  Using the process tracking feature of
`keepalived`, we can steer traffic directly to the node where the target
service is running.

keepalived/namespace.yaml

@@ -0,0 +1,6 @@
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: keepalived
+  labels:
+    app.kubernetes.io/name: keepalived