Multiple places for events
At the moment only one place can be specified per event.
To enable entering events e.g. a letter exchange with a sender and receiver location or a journey with a start and end point we will provide a new event class Move.
E9 Move -> P27 moved from -> E53 Place (e.g. start point of a journey, sender location of a letter exchange)
E9 Move -> P26 moved to -> E53 Place (e.g. end point of a journey, receiver location of a letter exchange)
If dates are used in the event the begin date would be associated with the first place and the end date with the second place.