Define entities and links between them to generate dynamic content on pages

[dennyabrain]

A lot of the fields specified in the frontmatter of blogs and updates are strings. Gatsby allows us to define them as entities that can then be queried in complex ways. For instance if the author of a blog post was an entity, this would allow us to query for all blog posts by an author. Since author is a person and would be listed on our team page, we could then provide a link on the team page that directs readers to all blog posts written by this person.
A similar thing could be done to link people with the projects they have worked on.

In scope for this feature would be the following :

1. Identify entities that must be defined
2. Make appropriate data related changes in the markdown files
3. Create queries for the new associations
4. Surface them in the UI