Calling AddRecipe on Update/Create shopping list does not set RecipeId field in database

[MikeChristensen]

When adding a recipe to a user's shopping list, the RecipeId field in the database should be set. Ie, each aggregated item in the shopping list should link to that recipe. This will allow UIs that can group shopping lists by the recipes that use those items.

Note: It is unclear if existing items of that same type will be overwritten with the new recipe ID, or a duplicate item will be created to preserve the amounts that go with each recipe. Possibly this can be user configurable.