Major Description
Allow Group Listeners that could handle events based on the @Group annotation within the POJO.
A single thread from a Group Listener thread pool would handle events for a specific Group within the node.
The Group Listener thread would need to lock the POJOs within the specific Group it is currently working on and prevent other Group Listener threads from accessing POJOs within that group.
POJOs within a Group should be handled in FIFO order
