Rabbitmq operator system test in envs without LoadBalancer capabilities

Log stderr and stdout when unable to enable plugins

Co-authored-by: Aitor Cedres <acedres@pivotal.io>

- Some minor refactor to not use PivNet registry image in every test spec
- PivNet registry image is used to test the ability to access private
registries. It is enough to test this in only one spec
- Ginkgo only needs one hyphen for arguments
Co-authored-by: Feroz Jilla <fjilla@pivotal.io>

Node Port service type is externally accessible via the Kubernetes node
IP. We can fetch this IP from the Kubernetes API. The port that
redirects to RabbitMQ pods via the service is the NodePort in the
Service Spec. The requirement now is that system tests can access
Kubernetes node IP; it is slightly similar to the previous assumption,
where the system tests relied on the IaaS to provide an external
accessible IP.

The intention of SynchronizedBeforeSuite is to initialise singletons
e.g. a database. It then provides a block to initialise clients, using
the data from the previous block if needed. Since we don't have a
singleton, we don't need to use this.

Increase system tests timeout and reduce parellel nodes

- Previous timeouts were enough for majority of the time;
however roughly 1 out of 5 times, some test cases will need
much longer time to create pods and wait until pods are ready.
Pods do eventually become ready, and tests will pass

Remove 5 nodes system tests

- our operator does not need to test clustering with
5 nodes and 3 nodes differently
- having one clustering test that can deploy a HA cluster
is enough

Rename ingress service to client service

- related to github issue #144

* [system tests] Retry amqps connection request

- the system tests have been failing with tls connectivity errors. The
retry logic gives RMQ more time to be able to serve the TLS connection requests.
The errors seem to be occurring because the connection request is sent
too early.

* [system tests] Relax timeouts, add more specific checks

- with the addition of new system tests (for example from #102), the
cluster is placed under further load and takes longer to complete
actions. This causes intermittent test failures when the timeout is
exceeded

- also run tests on 5 parallel nodes. This corresponds to the number of
high level specs in the tests
Co-authored-by: Chunyi Lyu <clyu@pivotal.io>

Adds operator scope namespace env variable

Rename apiGroup and operator namespace

- instead of pivotal-rabbitmq-system
- related to issue #109

Adds graceful termination design doc

- Change apiGroup from rabbitmq.pivotal.io to rabbitmq.com
- related to issue #109

* Better msg when not all pods ready to enable plugins

- related to issue #139

Remove p branding from labels and operator deployment name

* KEP to propose a new override section in CRD spec
* Only StatefulSet and ingress Service override atm
* Propose to use kubernetes [strategic patch merge(https://github.com/kubernetes/community/blob/master/contributors/devel/sig-api-machinery/strategic-merge-patch.md)

Remove restriction on spec.replicas size

- spec.replicas can be configured to 0 or greater than 0
instead of 1 or 3
- test cluster size 1, 3, 5 in system tests
- related to issue 131

- spec.replicas can be configured to 0 or greater than 0
instead of 1 or 3
- test cluster size 1, 3, 5 in system tests
- related to issue 131

- so that we can distinguish between 0 and null value
- related to issue #131

Co-authored-by: Aitor Cedres <acedres@pivotal.io>

Add a note to reviewers to remind about squashing

It is not required to set the `GOBIN` env variable. In environments where it is not set, the value `$GOPATH/bin` should be used.

Fixes #133

* Use MetalLB latest version and use a local Config

Kind-on-c repo is going to remove MetalLB. We have to use our own
configuration.

The make target will succeed and deploy MetalLB correcly in Kind.
However, the external IPs provided will not be reachable. It seems to be
a configuration of the local host network. In Mac it is not possible to
route traffic from the host to the containers; this is documented as a
Docker limitation for Mac.

We noticed some failures when a 2 second timeout was in place.
Increasing this to 5 seconds has passed 10 runs in a row now.

* Adds property `spec.TLS.SecretName`
* Expects the secret to contain the TLS cert and key for the RabbitMQ server, to be used for AMQP TLS
* If the property is set and the secret is found, changes the child resources by,
  * adding TLS properties to the ConfigMap
  * creating a Volume from the ConfigMap and attaching a VolumeMount onto the RabbitMQ pod so the TLS credentials reach the pod
  * opening the AMQP tls port on the ingress service
* Adds a system test that can be used to demonstrate the TLS workflow

Make targets to start delve debugger

In the spirit of keeping our commit history relevant and navigable, reviewers should also review the commit list presented in a PR. If some or all commits can be squashed, they should suggest so. If not all commits should be squashed, the reviewer should suggest to rebase the branch and re-push.

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