removed private component for facade class
Added single word parsing functionality.
Fixed minor bugs with repeated keywords. Example: ("by wed by tues by fri")
Will only take the first instance now.
added the commandExecutor
added the LogicFacade
added Stack class to Storage for undo and redo.
Added methods to Command.
Modified TaskList.
Merge remote-tracking branch 'origin/yongkai'
Merge remote-tracking branch 'origin/jiashun'
Merge remote-tracking branch 'origin/krystal'
Allow CommandLineController and PhantomController to use LogicFacadeDummy for testing
Added TodayView fxml file and space in OverallView fxml file to put the TodayView