introduce parkingAreaReroute attribute 'visible'

[namdre]

Currently, vehicles that encounter a reroute with parkingAreaReroute definitions have full knowledge regarding occupancy of the included parkingAreas. The attribute 'visible' models eye contact or an information system that shows occupancy status.

The attribute 'visible' (default 'false') shall be introduced with the following semantics:

• if a vehicle reaches the position of a parkingArea it always knows its occupancy status
• for all other parkingAreas it only knows the occupancy status if visible=true
• for all parkingAreas with unknown occupancy status, the assumed occupancy value shall be chosen randomly from [0,capacity[ (always assuming at least one space might be free) before determining an alternative (a better model with memory may be introduced later)