Structure:

# Travel Points of Interest type
# Each entry represents a type of interesting locations to visit.
key = {

	# Effect that gets triggered when a character visits a POI for the first time
	# Root - Traveling character.
	# scope:province - province being visited
	on_visit = {}

	# Optional, effect which is run monthly period to find which provinces have this type of point of interest
	# If provinces are also added/removed via effects (`add_travel_point_of_interest`, `remove_travel_point_of_interest`),
	# they need to be valid/invalid in this effect too.
	#
    # use add_to_list = provinces to return which provinces are valid
	build_province_list = {}
}
