* Add EventsGetter to KubeClient to enable to sending K8S events
* Add eventRecorder to the controller, initialize it and hand it down to cluster via its constructor to enable it to emit events this way
* Add first set of events which then go to the postgresql custom resource the user interacts with to provide some feedback
* Add right to "create" events to operator cluster role
* Adapt cluster tests to new function sigurature with eventRecord (via NewFakeRecorder)
* Get a proper reference before sending events to a resource
Co-authored-by: Christian Rohmann <christian.rohmann@inovex.de>