Vendor middleware_automation.keycloak collection

Needed for keycloak_authentication_v2, to manage Keycloak
authentication flows (e.g. the CCCHH browser flow) as YAML.
Chosen over community.general's own copy of the module (deprecated in
favor of this collection, and limited to 4 sub-flow levels there vs.
10 here).

ansible_collections/middleware_automation/keycloak/docs/index.rst

@@ -0,0 +1,34 @@
+.. Red Hat middleware_automation Keycloak Ansible Collection documentation main file
+
+Welcome to Keycloak Collection documentation
+============================================
+
+.. toctree::
+   :maxdepth: 2
+   :caption: User documentation
+
+   README
+   plugins/index
+   roles/index
+   Changelog <CHANGELOG>
+
+.. toctree::
+   :maxdepth: 2
+   :caption: Developer documentation
+
+   Developing <developing>
+   Testing <testing>
+   Releasing <releasing>
+
+.. toctree::
+   :maxdepth: 2
+   :caption: Middleware collections
+
+   Keycloak / Red Hat Single Sign-On <https://ansible-middleware.github.io/keycloak/main/>
+   Infinispan / Red Hat Data Grid <https://ansible-middleware.github.io/infinispan/main/>
+   Wildfly / Red Hat JBoss EAP <https://ansible-middleware.github.io/wildfly/main/>
+   Tomcat / Red Hat JWS <https://ansible-middleware.github.io/jws/main/>
+   ActiveMQ / Red Hat AMQ Broker <https://ansible-middleware.github.io/amq/main/>
+   Kafka / Red Hat AMQ Streams <https://ansible-middleware.github.io/amq_streams/main/>
+   Ansible Middleware utilities <https://ansible-middleware.github.io/common/main/>
+   JCliff <https://ansible-middleware.github.io/ansible_collections_jcliff/main/>