ISIS-753: should register JDO versions of EventBusService in the apps...

... not the default versions.

In addition, extended the ToDo  (quickstart) app to demonstrate the use of event bus service.
ISIS-753: example of EventBusService

added to the todo (quickstart) application.
ISIS-749: less noisy DataNucleusSimplePersistAlgorithm...

... for the makePersistent() method when persists (move from INFO to DEBUG).