Create PantryItem API

[iisisrael]

PantryItem records need an API...

• A PantryItem defines the parameters of a food or product that can be provided to a Client or Household during a ServicePantry event
• The actual food or product that is provided, a ServicePantryItem, is created from a PantryItem, like a template or default, then the ServicePantryItem can be adjusted to the use case
  ** For example, a PantryItem record is named "Rice" with a default size of 1 LB
  ** A ServicePantry record is created for Client Jane Doe when she arrives for a food give-out
  ** A ServicePantryItem is created from the "Rice" PantryItem, renamed "Rice Pack", updated to 5 LBS, and associated with the ServicePantry record (the PantryItem record does not change)
• PantryItem records should be allowed to be updated at any time, as they are not historical event records