Revert "Revert "Updated Store class and associated Class files""

This reverts commit 84d2a9781f446ee8c5a1cc42a3d6d419139a1dda.

Conflicts:
	PizzaOrderingSystem/src/main/java/cs414/pos/Store.java
	PizzaOrderingSystem/src/test/java/cs414/pos/StoreTest.java
	PizzaOrderingSystem/testSave.ser