begin ui
add if statment for main menu of ui
add if statment for second menu
add create line method for ui
add edit line method for ui
add delete line method for ui
add create station method in ui
add edit station method in ui
add delete station method in ui
add create stop method in ui
add edit stop method in ui
add delete stop method in ui
add query lines and stations methods in ui
add stations for line query method in ui
add lines for station query method in ui
move stops for line method to line class
move lines for station method to station class