Add a guide for creating a new repository

[mcmire]

Creating a new repository is not as simple as pressing the "plus" button on GitHub. There are two things that we ought to communicate for people who want to create a repo. First, there are a series of settings that an admin should make to ensure that the repo is configured in a standard way. Right now, these steps live in a private doc. Furthermore, if the repo will represent a package, then the module template should be used to create the repo. This ensures that the package is set up in a standard way.

Acceptance Criteria

• The guide mentions and links to the private repo configuration doc
• The guide mentions the module template for package repos

[mcmire]

We should also include instructions for people who want to publish packages. Specifically, they should reach out to the npm-publishers group to create an NPM token.