UIL2 does not close client sockets when the service is shutdown

The UIL2 service does not close sockets when the service is stopped.

Normally this is not a problem because the JBoss process ends which does close the sockets.

There are two parts to this fix:
1) JMSDestinationManager.stopServer()
needs to iterate over connected clients and invoke the client IL's close method

2) UIL2 needs to implement close()

The other ILs also need checking to make sure they implement close properly when the
server (through stopping service) unilaterally ends the client's connection.