✨ Internal train network structure

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

tests/CMakeLists.txt

@@ -3,11 +3,18 @@ add_subdirectory(googletest)
 add_executable(
 	test_trenesis
 	trenesis/test.cpp
+	trenesis/network/graph.cpp
 )
 
 target_link_libraries(
   test_trenesis
+  trenesis
   GTest::gtest_main
+  GTest::gmock_main
+)
+
+include_directories(
+	assets
 )
 
 include(GoogleTest)