This allows anyone to visit the URL and be added to a (hopefully read-only) team. Uses PHP 7 and Redis/Memcached.
GITHUB_CLIENT_ID- Your GitHub applications's client ID.GITHUB_CLIENT_SECRET- Your GitHub application's client secret.GITHUB_USER_TOKEN- A personal access token with theadmin:orgpermission.GITHUB_TEAM- The ID of the team people should be added to.GITHUB_CALLBACK- The callback URL to redirect from GitHub to.