Please provide basic usage instructions for this action

[etcadinfinitum]

Surprisingly, this repository doesn't have a README; this is a huge barrier to usability for instructors who haven't been following community chatter about this feature, and stands in stark contrast to GitHub's general philosophy about beautiful, robust, and useful documentation. Please create a README (or GitHub Pages site?) which, at a minimum, provides documentation of the following:

• How this action works in tandem with the autograding config section of the Classroom assignment template UI
• Configuring test cases in the Classroom environment (if this is how the tests should be configured?)
• Setting up this action to run in student repositories

[stevenbitner]

I've taken a stab at a README for this project. It is in my fork at https://github.com/stevenbitner/autograding. Hope it helps someone.