Hide open/closed in UI for new general examination regulations

src/util/strings.hpp

src/view/boundary_window/boundary_window.cpp

src/view/input_window/load_file_view.cpp

src/view/main_window/export_rwthonline.cpp

src/view/main_window/main_window.cpp

src/view/main_window/min_max_point_screws.cpp

src/view/main_window/students_tab.cpp

src/view/main_window/task_tab.cpp