Add a Galleon layer for messaging integration with a remote ActiveMQ broker

This issue is created to track the creation of a Galleon layer to make it easy to configure a connection with our preferred remote broker, ActiveMQ Artemis.

The layer will provide a messaging-activemq subsystem with appropriate configuration for connection to a remote Artemis-based broker. It will also provide ancillary configuration resources, e.g. an outbound-socket-binding. Necessary dependencies needed to support this use case, e.g. the resource-adapters subsystem, will also be provided.