Addon: Stream all Kubernetes events to a topic

[solsson]

A quite interesting log with messages like (kubectl -n test-kafka logs -l test-target=events-topic):

{
  "type": "MODIFIED",
  "object": {
    "kind": "Event",
    "apiVersion": "v1",
    "metadata": {
      "name": "pzoo-0.14d7585c3d972d2d",
      "namespace": "kafka",
      "selfLink": "/api/v1/namespaces/kafka/events/pzoo-0.14d7585c3d972d2d",
      "uid": "e0ed084c-784d-11e7-a1b0-42010a840078",
      "resourceVersion": "108989",
      "creationTimestamp": "2017-08-03T13:15:53Z"
    },
    "involvedObject": {
      "kind": "Pod",
      "namespace": "kafka",
      "name": "pzoo-0",
      "uid": "c4d1c2e6-784d-11e7-a1b0-42010a840078",
      "apiVersion": "v1",
      "resourceVersion": "469107",
      "fieldPath": "spec.containers{zookeeper}"
    },
    "reason": "Unhealthy",
    "message": "Readiness probe failed: ",
    "source": {
      "component": "kubelet",
      "host": "gke-eu-west-3-default-pool-f275612a-f7m1"
    },
    "firstTimestamp": "2017-08-03T13:15:53Z",
    "lastTimestamp": "2017-08-05T04:54:23Z",
    "count": 592,
    "type": "Warning"
  }
}

(#31 should take note about this particular event)

Reopens #39.

Includes RBAC policy from #59

[solsson]

Tried to improve error handling, for example when RBAC is missing, but with no real success. You basically need to exec to the pod (which is most likely crashlooping fast) to try the curl manually. Status noted in fc5a836.

TODO test if the curl error (with -f) gets into the topic, thus breaking consumers that assume they will get JSON. Status on that is in d628275.