✨ Internal train network structure

- Defines Network, StopArea, StopPoints and JourneySections
- Loads them from json using the build_from_json method

lib/trenesis/geojson.cpp

@@ -0,0 +1,7 @@
+#include "geojson.h"
+
+namespace trenesis {
+	Point::Point(double longitude, double latitude)
+		: longitude(longitude), latitude(latitude) {
+		}
+}