Add regenerate controller pod script

When developing using containerized mode, you'd need to go over the
steps on [1] quite a few times. This script just automates the process
for ease of development.

[1] https://docs.openstack.org/kuryr-kubernetes/latest/installation/devstack/containerized.html

Change-Id: I034b1d79941e1f986dd7c4991c7c971bb202bf75

contrib/regenerate_controller_pod.sh

@@ -0,0 +1,17 @@
+#!/bin/bash
+
+set -o errexit
+
+KURYR_DIR=${KURYR_DIR:-/opt/stack/kuryr-kubernetes}
+KURYR_CONTROLLER_NAME=${KURYR_CONTROLLER_NAME:-kuryr-controller}
+
+function build_tagged_container {
+    docker build -t kuryr/controller -f $KURYR_DIR/controller.Dockerfile $KURYR_DIR
+}
+
+function recreate_controller {
+    kubectl delete pods -n kube-system -l name=$KURYR_CONTROLLER_NAME
+}
+
+build_tagged_container
+recreate_controller