allow user to easily override the transaction node identifier

Add

node-identifier="${jboss.tx.node.id:1} 

to the default WF Config files.

Allows a user to then set -Djboss.tx.node.id to something like a pod name during startup in a script

IMPORTANT: The ID must be globally unique still so scenarios where there is more than one process on this box will need to use something to ensure there is an identifier that is unique