steps to enable TLS for attestations

TLS-enable.txt

1. create DNS "A" record (link ip address with FQDN)
2. make sure port 443 is open
3. sudo apt install nginx
4. stop attestation-service (so we can get certificate on default port 80)
5. sudo systemctl start nginx
6. sudo systemctl enable nginx
7. https://certbot.eff.org/instructions?ws=nginx&os=ubuntubionic
        (sudo snap install --classic certbot; sudo ln -s /snap/bin/certbot /usr/bin/certbot; sudo certbot --nginx)
8. sudo vi /etc/nginx/sites-available/default (doc root change to /dev/null so that http://ipaddress will fail)
9. attestation.config should point to new port (8080)
10. attestation-service should use new port (8080)
11. sudo systemctl restart nginx
12. update CELO_ATTESTATION_SERVICE_URL (only used by metadata)
13. start attestation-service
14. update metadata
15. update nexmo callback URLs
16. make backup of “default” file
NOTE: to delete a no longer needed certificate: "sudo certbot delete" or "sudo certbot delete --cert-name example.com"