[Emergency] Refractor Model class

[rockman007372]

• [x] Refractor Person class to PowerCard class
• [x] Refractor UniquePersonList to UniqueCardList
• [x] Refractor Addressbook to Deck
• [x] Refractor ReadOnlyAddressBook to ReadOnlyDeck
• [x] Refractor Model's methods based on DeckModel (Keep the class name Model, but refractor all the methods)
• [x] Refractor ModelManager's methods based on DeckModelManager (Keep the class name ModelManager, but refractor all the methods)

[unfazing]

Make sure the UI and build is working before every commit

• run the build and fix any issues (e.g. checkstyle violations)
• run the main.main() and see GUI appear without any javafx error logged