ACME Support

[zenhack]

As noted in #9, we have HTTPS support, but still need to be able to automatically retrieve certs via ACME. I'm opening a separate issue for that so I can close the HTTPS issue.

So far I've been having trouble even getting a cert out of the lego command line tool; output below. Obv. this makes it hard to move forward with automating things.

++ lego --accept-tos --server https://acme-staging-v02.api.letsencrypt.org/directory --email ian@zenhack.net --dns cloudflare --domains thelibrary.house --domains '*.thelibrary.house' run
2023/05/06 21:52:34 [INFO] [thelibrary.house, *.thelibrary.house] acme: Obtaining bundled SAN certificate
2023/05/06 21:52:35 [INFO] [*.thelibrary.house] AuthURL: https://acme-staging-v02.api.letsencrypt.org/acme/authz-v3/6384827634
2023/05/06 21:52:35 [INFO] [thelibrary.house] AuthURL: https://acme-staging-v02.api.letsencrypt.org/acme/authz-v3/6384827644
2023/05/06 21:52:35 [INFO] [*.thelibrary.house] acme: use dns-01 solver
2023/05/06 21:52:35 [INFO] [thelibrary.house] acme: Could not find solver for: tls-alpn-01
2023/05/06 21:52:35 [INFO] [thelibrary.house] acme: Could not find solver for: http-01
2023/05/06 21:52:35 [INFO] [thelibrary.house] acme: use dns-01 solver
2023/05/06 21:52:35 [INFO] [*.thelibrary.house] acme: Preparing to solve DNS-01
2023/05/06 21:52:35 [INFO] [thelibrary.house] acme: Preparing to solve DNS-01
2023/05/06 21:52:35 [INFO] [*.thelibrary.house] acme: Cleaning DNS-01 challenge
2023/05/06 21:52:36 [WARN] [*.thelibrary.house] acme: cleaning up failed: cloudflare: unexpected response code 'SERVFAIL' for _acme-challenge.thelibrary.house. 
2023/05/06 21:52:36 [INFO] [thelibrary.house] acme: Cleaning DNS-01 challenge
2023/05/06 21:52:36 [WARN] [thelibrary.house] acme: cleaning up failed: cloudflare: unexpected response code 'SERVFAIL' for _acme-challenge.thelibrary.house. 
2023/05/06 21:52:36 [INFO] Deactivating auth: https://acme-staging-v02.api.letsencrypt.org/acme/authz-v3/6384827634
2023/05/06 21:52:36 [INFO] Deactivating auth: https://acme-staging-v02.api.letsencrypt.org/acme/authz-v3/6384827644
2023/05/06 21:52:37 Could not obtain certificates:
	error: one or more domains had a problem:
[*.thelibrary.house] [*.thelibrary.house] acme: error presenting token: cloudflare: unexpected response code 'SERVFAIL' for _acme-challenge.thelibrary.house.
[thelibrary.house] [thelibrary.house] acme: error presenting token: cloudflare: unexpected response code 'SERVFAIL' for _acme-challenge.thelibrary.house.