Make recipes usable as ingredient in other recipes

[Yann-BUTSCHER-EIRL]

We need to be able to create new recipes that are composed of other recipes.

For example if we make home-made tomato sauce we might want to add it to the pasta alla bolognese recipe.

Todo

• Create an ingredientable trait
• Implement it in for the ingredient class
• Implement it in for the recipe class
• Update the relationship in recipe to take an ingredientable entity
  • Use polymorphism for this
• Update the recipe CRUD for it to use the new relationship
  • CREATE
  • READ
  • UPDATE