Certificate renewal requires nginx restart

[vanwars]

Need to fix this error (copied below), which happens when the cronjob tries to renew the certificate. In order to get it to work, I had to first stop nginx. Then renew the certificate. Then start nginx.

Fixed for now, but cronjob needs to be edited to account for this need at some point in the future.

Attempting to renew cert (xili.localground.org) from {{path_omitted}} produced an unexpected error: Problem binding to port 443: Could not bind to IPv4 or IPv6.. Skipping.
All renewal attempts failed. The following certs could not be renewed:
  {{path_omitted}}/fullchain.pem (failure)