Refactored sorting.
Added test to verify all horizon areas (outside exceptions) are marked
as station areas.
Added test to verify shuttle areas are not marked as station areas.
Refactored how the area sorting var is made and used.
Added a global list of all areas.
Replaced the outside turfs with exoplanet ones for the digsite.
Fixed some exoplanet areas not having an exoplanet base turf.
Wrote a unit test for exoplanet areas to ensure they have an exoplanet
base turf.