Populate Dev Guide

[jared321]

We should populate the Developer Guide with a minimal, simple amount of information needed for the small set of developers to collaborate effectively in the repo and use its infrastructure.

I will start off by adding in rough drafts of basic information and will ask other developers to review.

[jared321]

Add in a typos GH action and a link checking GH action to facilitate populating and maintaining the documentation. It's OK if the typo check isn't checking the code in the repo at first.

Progress

• Add typo checking action #18
• Add link checker action #19

Note that the link checker action was run automatically this Sunday morning as desired.