As a customer/visitor, I want to be able to view all available products so I can pick from a variety.

[ksantiago]

Backend:

• write Express routes to serve all products
• build Product model

Frontend:
(note: product state can either be a single product or all products)

• write a component to display a list of all products
• write a sub-reducer to manage product state (see above note)
• display allProducts component when url matches '/products'