Compare shopping list to pantry

[blahosyl]

User goal: adjust the shopping list based on the ingredients already available

Possible implementation:

• At the end of the program, before the goodbye screen, ask user if they want to compare shopping list to pantry
  • validate answer (Y/N)
• loop through each ingredient, and ask how much they have
  • can only enter a float (can use a similar validation as for dish selection)
  • subtract entered number from quantity on shopping list
  • if shopping list quantity <= zero, delete item from shopping list
• print revised shopping list
• make new function a method of the ShoppingList object
• integrate new function into existing flow

[blahosyl]

Add logic for case where all ingredients are in the pantry, so shopping list becomes empty