Set up and document Drools Quarkus extension

[mariofusco]

This task involves a few steps that have to be performed partially before and partially after the release of Drools 10.0. In particular:

• BEFORE the release it's necessary to configure the extension's metadata as described here. As explained in that page, some other metadata are also collected from the pom.xml file of the extension's runtime, so it will also need to be at least checked or fixed.
• AFTER the release the extension has to be added to the extensions catalog.

Moreover a guide documenting how this extension works should be added here.

[mariofusco]

Drools extension's metadata fixed with https://github.com/apache/incubator-kie-drools/commit/b376fa433d6f91933cc9044e5b42284692581822

[mariofusco]

Documentation is here https://github.com/quarkusio/quarkus/commit/63601650838ce9167d6cc20c1454c2e46e4462a8 I will send the contribution to the quarkus repo when the drools major release will be out.