Remove unsupported note from README.

* Add scripts to regenerate the Wiki sidebar doc on new API versions

* Fix generated URLs to not have the .asciidoc suffix

This allows linking to the wiki pages rather than the raw asciidoc file

Bumps [sigs.k8s.io/kustomize/kustomize/v3](https://github.com/kubernetes-sigs/kustomize) from 3.9.1 to 3.9.2.
- [Release notes](https://github.com/kubernetes-sigs/kustomize/releases)
- [Changelog](https://github.com/kubernetes-sigs/kustomize/blob/master/docs/v2.1.0_changelog.md)
- [Commits](https://github.com/kubernetes-sigs/kustomize/compare/kustomize/v3.9.1...kustomize/v3.9.2

)
Signed-off-by: dependabot[bot] <support@github.com>

* Add make tests target
* Use make targets in pr workflow

Bump controller-runtime to v0.8.0

Also bumps k8s dependecies to 0.20.1 & fixes test that break due to k8s
v1.20 API changes

* Run system tests against multiple RabbitMQ versions

* Test against latest 3.8 RC

- RabbitmqConf can be interpreted as rabbitmq.conf
which is not what the test asserts on

The new port matches the one listed in
https://github.com/prometheus/prometheus/wiki/Default-port-allocations

This PR allows auto generation of the API Reference documentation from the api/ directory in the repo.

Running make api-reference, or any other make target that requires auto generation of code, will cause the reference docs to be regenerated. They now live at docs/api/rabbitmq.com.ref.asciidoc. This format can be interpreted by GitHub and rendered as HTML.

Allowing this documentation to be autogenerated will prevent API elements/descriptions being updated without the API reference docs being updated alongside.

This PR also includes a GitHub Action to take the generated Asciidoc and insert it into our GitHub Wiki, so that our API reference is neatly packaged together with the source code.

Bumps [github.com/go-stomp/stomp](https://github.com/go-stomp/stomp) from 2.1.0+incompatible to 2.1.2+incompatible.
- [Release notes](https://github.com/go-stomp/stomp/releases)
- [Changelog](https://github.com/go-stomp/stomp/blob/master/breaking_changes.md)
- [Commits](https://github.com/go-stomp/stomp/compare/v2.1.0...v2.1.2

)
Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

* Place RabbitMQ configuration in confd

Files places in confd are loaded after 'rabbitmq.conf' is loaded,
allowing the user configuration to take precedence. The ConfigMap has
keys without any numeric prefix because file naming is done in
StatefulSet's pod template volume mounts. This allows flexibility in the
future, shall we decide we rename or change the numeric prefixes.

This commit also adds a condition to decide whether to include the
server ConfigMap as a volume. This happens if RabbitMQ env or advanced
config are set in the RabbitmqCluster Spec. The server conf is partially
projected into a volume that is always specified.

* Use a string builder to generate RMQ configuration

String builder is more efficient than a byte buffer for strings.

* Rename additionalConfig to userDefinedConfiguration

The previous name could set an expectation to be a 1-to-1 mapping
between the file and the contents in `.spec.rabbitmq.additionalConfig`.
This was not intended, as this file can contain other configuration,
generated based on the user input.

Reverted the change that used string concatenation instead of multi-line
string in test expectations.

Make logger configurable

Before this commit, the cluster operator always used a logger dev mode,
even in production.

After this commit, the logger is prod mode by default.

When developing locally deploying the operator using `make deploy-dev` and
`make deploy-kind`, the logger will use dev mode.

Futhermore, users can now configure more zap flags (see
https://github.com/kubernetes-sigs/controller-runtime/blob/66537ca5b7439b06f2f3b08901640f934834c9a1/pkg/log/zap/zap.go#L227-L233)
For example, they can set the log level.

* Use logger from context in Reconcile()

- with controller-runtime 0.7, Reconcile() takes a
context with a logger. The logger is pre populated with
controller name, gvk, object name and namespace.

* Use LoggerFrom alias

Also, remove logger from method signatures since it's already part of
context.

* Remove redundant namespace and name from logs
Co-authored-by: David Ansari <david.ansari@gmx.de>

Before this commit, existing pod annotations took precedence over
updated annotations (e.g. prometheus port).

This commit fixes issue 2 in
https://github.com/rabbitmq/cluster-operator/pull/533#pullrequestreview-561162856

- this is related to bug reported in: #537
-  k8s allows pvc template in sts to not have namespace
specified and assumes it's the same namespace as the sts
- operator needs to set namespace because controller
reference can only be set when both object name and
namespace are specified

* Add prom tls example

Bump controller-runtime to 0.7 and k8s.io dependencies to v.0.19.2

* Update leader election role to have permission for leases.coordination.k8s.io instead of ConfigMap. Related controller runtime change: kubernetes-sigs/controller-runtime#1144
* Use client.Object instead of runtime.Object in controller runtime helper methods. A number of controller runtime methods that previously took runtime.Object & internally type-asserted them to metav1.Object now take client.Object and client.ObjectList. Related controller runtime change: kubernetes-sigs/controller-runtime#1195
* Update how envTest starts the test manager since Manager.Start() now takes context instead of a channel

- started manager will be stopped when ctx is cancelled

- Reconciler interface has changed in controller
runtime 0.7; Reconcile() takes an additional
context.Context, which can be used throughout
Reconcile() function.
- CreateOrUpdate() needs to in client.Client
explicitly

- controller runtime helper functions use client.Object
in version 0.7

- controller runtime 0.7 has changed leaderlock from
ConfigMap to ConfigMapsLeasesResourceLock

fix standard port for Prometheus

Merge pull request #536 from rabbitmq/dependabot/go_modules/sigs.k8s.io/kustomize/kustomize/v3-3.9.1

Bump sigs.k8s.io/kustomize/kustomize/v3 from 3.8.8 to 3.9.1

As part of [TGIR S01E09](https://www.youtube.com/watch?v=y2HAJBiXsw0),
we found that the ignore strategy was not ideal for production use cases
where a network partition occurred due to the necessity of manual
intervention.

In addition, the readiness probe does not account for the fact that a
pod is partitioned, meaning that in the case of a 3-node quorum queue cluster with a
2-1 network partition, 1/3 of the traffic will be routed via the Service
to pods that cannot serve traffic due to them not establishing quorum.

By contrast, the pause_minority strategy will stop the RabbitMQ app,
meaning that the Service will no longer redirect traffic to the pod
until it regains quorum.

Merge pull request #535 from rabbitmq/dependabot/go_modules/github.com/eclipse/paho.mqtt.golang-1.3.1

Bump github.com/eclipse/paho.mqtt.golang from 1.3.0 to 1.3.1

Merge pull request #526 from rabbitmq/dependabot/go_modules/github.com/go-stomp/stomp-2.1.0incompatible

Bump github.com/go-stomp/stomp from 2.0.8+incompatible to 2.1.0+incompatible

Bumps [sigs.k8s.io/kustomize/kustomize/v3](https://github.com/kubernetes-sigs/kustomize) from 3.8.8 to 3.9.1.
- [Release notes](https://github.com/kubernetes-sigs/kustomize/releases)
- [Changelog](https://github.com/kubernetes-sigs/kustomize/blob/master/docs/v2.1.0_changelog.md)
- [Commits](https://github.com/kubernetes-sigs/kustomize/compare/kustomize/v3.8.8...kustomize/v3.9.1

)
Signed-off-by: dependabot[bot] <support@github.com>

Bumps [github.com/eclipse/paho.mqtt.golang](https://github.com/eclipse/paho.mqtt.golang) from 1.3.0 to 1.3.1.
- [Release notes](https://github.com/eclipse/paho.mqtt.golang/releases)
- [Commits](https://github.com/eclipse/paho.mqtt.golang/compare/v1.3.0...v1.3.1

)
Signed-off-by: dependabot[bot] <support@github.com>