Alter atmibroker-tx to support a cluster of transaction managers

Currently, a single transaction manager is configured in the Environment.xml

To support fail over of transaction manager instances it would be useful to be able to configure the Environment.xml with a list of transaction manager details which can be "failed over" to in the case of app server failure.

Note when several transaction managers are in use the recovery manager must also be configured as a HA singleton service and the transaction managers must be configured to use the JDBC object store

A change will also need to be made to the recovery manager configuration to indicate the additional recovery nodes:

jbossts-properties.xml node id
com.arjuna.ats.jta.xa.recovery.node[_1]=1