Don't persist ReservationStarted-/ -EndedEvents
adding event store options to PortalServerConfig
Renaming PortalEventStoreService to PortalEventStore
extending ReservationManager

Adding ability to search for reservations by timestamp
small refactorings in PortalEventStoreHelper

renaming of variables
Removing unnecessary tests from ReservationEventStoreImplTest
adapting PortalEventStoreImplTest to new implementation
adapting federator module to new event dispatching logic

dispatching of federated events is now processed in the FederatedPortalEventDispatcher.

implementing inherited methods in FederatedReservationManager
adding PortalEventDispatcher

the dispatcher is registered at the PortalEventBus and dispatches events to the appropriate ReservationEventBus instances.
binding and starting the event dispatcher
removing event dispatching from ReservationEventBus

the logic is moved to the PortalEventDispatcher.

Cleaning the unit test hence these kind of tests have to be executed for the PortalEventDispatcherImpl

TODO: adapt this unit test for the event dispatcher
adding new storeMethods to portal implementations of event store

using new store methods to store the events timestamp (if available) as event timestamp in the event store
RSPersistenceJPA: query parameter must be a Long not a DateTime
catching empty reservation keys

method returns null in these cases as the doc comment in the interface suggests.
formatting event store code
don't generate ReservationEndedEvents before actual reservation end
using portal server config to enable/disbale portal event store

when disabled, the PortalEventStore exists but did not store any events. The service isn't started in this case.