add Model
add Resettable
add ButtonPanel
add Java3_Lesson06
add GUIDemo
add package-info files
add ActionListener to GUIDemo
add Resettable
add ActionPanel
implement resetComponents method
add ActionPanel to GUIDemo
add MainPanel
remove ActionPanel from GUIDemo
add Model
add getters and setters
add Model to GUIDemo
add ItemListeners to ActionPanel
add paint() method to GUIDemo
finish java3_Homework06