ListTimersCommand may use BoundaryEvent name to compose timer name

As SLATimers are now adding [SLA] prefix to the node name in SLA timers for returning the list of timers, for Boundary timers a similar approach could be followed.

Currently, when there is more than one boundary timer over the same node, all of them are returned with the same name (node name). It would be more useful to add also the boundary event name.