迁移了原来的nav2包；新增基于obstacle_scanner构建costmap的nav2，暂未实际测试

src/navigation/gc_navigation2_real/CMakeLists.txt

@@ -0,0 +1,23 @@
+cmake_minimum_required(VERSION 3.8)
+project(gc_navigation2_real)
+
+if(CMAKE_COMPILER_IS_GNUCXX OR CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+  add_compile_options(-Wall -Wextra -Wpedantic)
+endif()
+
+# find dependencies
+find_package(ament_cmake REQUIRED)
+
+install(
+  DIRECTORY launch config params maps behavior_tree
+  DESTINATION share/${PROJECT_NAME}
+)
+
+if(BUILD_TESTING)
+  find_package(ament_lint_auto REQUIRED)
+  set(ament_cmake_copyright_FOUND TRUE)
+  set(ament_cmake_cpplint_FOUND TRUE)
+  ament_lint_auto_find_test_dependencies()
+endif()
+
+ament_package()