[FEATURE] Fix up schema

[dwreeves]

Overview

We have a schema document on Google Drive. We should make sure we implement it because right now we just have a flat table.

Requirements for issue

• Look at existing data out there (see the about page in the docs for more), and get a good idea of what we want to do.
• Add to schema doc we currently have, validate it, critique it, etc. https://docs.google.com/document/d/1fcIQoyUuwTtM0Ik8U43B6qkCHTL8ttT7VsRCne9vyBs/edit#
• Implement the new schema.
• Come up with a list of questions about our attempt at a schema for other stakeholders.

[DMalone87]

Schema is currently being worked on in the Data Council Meetings (minutes here).

Tentative schema can be found in the Schema Development workspace as NPDC.yml.