[Feature] Add product to data model?

[TimidRobot]

Problem

The CC Legal Tools include four "products", one in the licenses category and three in the publicdomain category:

1. licenses:
   1. Licenses (by, by-nc, by-nc-nd, by-nc-sa, by-nd, by-nc-nd/by-nd-nc, by-sa, devnations, nc, nc-sa, nc-sampling+, nd, nd-nc, sa, sampling, sampling+)
2. publicdomain:
   1. CC0 (zero)
   2. PDM (mark)
   3. Certificate (certificate)

Each of these products have their own versioning.

The lack of product in the data model makes it difficult to differentiate the Public Domain products (ex. on the Public Domain List page).

Description

1. Determine best term (ex. product)
2. Add product to data model

Alternatives

If the only location that having "product" would improve application behavior is the Public Domain list, it may not be worth updating the data model.