Webhook to commit vals to GitHub and sync code from GitHub back to Val Town

This example val is synced to this GitHub repo

1. Fork this val
2. Edit config.json to point to the repo and vals you plan to sync
3. Create a new repo on GitHub to sync to
4. Add a webhook to your repo that points to this val's /deploy route, e.g. https://username-<ID>.web.val.run/deploy
   • Create a secret for your webhook
   • In this val's Environment Variables, add that secret
5. On GitHub, create a new personal access token
   • Ensure the token has read/write access to Contents for the repo
   • Copy the access token and add that as the GITHUB_TOKEN env var in this val

This is the next version of https://www.val.town/v/jxnblk/gitHubSync

Note: This will currently only work with non-project vals until the SDK supports projects.

• Basic webhook handler w/ secrets
• GitHub commit util
• Val Town SDK to write vals
• Make private val to call sync to GitHub webhook
• auth middleware for export and deploy routes
• Add env vars
• Set up test vals
• Monkey test
• Add setup instructions to readme