Up the doc game here

[cansavvy]

We need more docs here that explain how this works so people can contribute.

Here's the basics:

1. main.sh is the core of the action it is called by action.yml
2. main.sh copies over and runs the scripts in the scripts folder
3. report-maker.yml calls action.yml and handles the commenting on the PRs.

[howardbaik]

Addressed in #35