[ANNOUNCE] Apache Solr Operator v0.3.0 released

[Houston Putman <ho...@apache.org>]

The Solr PMC is pleased to announce the release of the Apache Solr Operator v0.3.0.

The Apache Solr Operator is a safe and easy way of managing a Solr ecosystem in Kubernetes.

This release contains numerous bug fixes, optimizations, and improvements, some of which are highlighted below. The release is available for immediate download at:

<https://solr.apache.org/operator/downloads.html>


### Solr Operator v0.3.0 Release Highlights:

* The Solr Operator is now an Apache project managed by the Apache Solr PMC.
* The CRDs are now under the solr.apache.org group instead of solr.bloomberg.com.
* The Solr Operator now fully supports running Solr in a secure and locked down way:
* Basic Auth support is now built in when requested in the SolrCloud CRD
* Solr can be run with TLS (optional mTLS, if provided to the operator)
* More helm chart options are provided to customize running the Solr Operator
* The Zookeeper Operator is now up-to-date with the most recent release, v0.2.9.
* It can now be installed as a helm-chart dependency with the Solr Operator.
* Users can now provide custom Solr log4j.xml and Prometheus Exporter config xml configMaps
* Fixed a bug in custom probes for Solr pods
* Solr pod shutdown is more graceful, has better coordination between Kubernetes and Solr.
* SolrCloud can now be used with the Kubernetes HPA to autoscale Solr Cloud pods.

A summary of important changes is published in the documentation at:

<https://apache.github.io/solr-operator/docs/upgrade-notes.html>

For the most exhaustive list, see the full release notes in the Github Releases or by viewing the git history in the solr-operator repo.

<https://github.com/apache/solr-operator/releases/tag/v0.3.0>


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