make an acme-dns log when used via systemd

[jvanasco]

right now logging goes into syslog and can be a bit messy to parse/understand as many services output there. a dedicated log would be nice.

[joohoi]

This is very true, and it's on the TODO list in readme. Needs an (mental) priority bump for the stated reasons however. I'll leave this issue up for reminder.

[cbricart]

actually, when started under systemd any logging should got to stdout/stderr (that also applies to running containerized) - systemd will catch those outputs and send them to systemd-journald(8) which may then be comfortably queried with journalctl(1):
$> journalctl -u acme-dns.service

[LinuxCuba]

`root@certbot:/# systemctl status acme-dns.service

• acme-dns.service - Limited DNS server with RESTful HTTP API to handle ACME DNS challenges easily and securely
  Loaded: loaded (/etc/systemd/system/acme-dns.service; enabled; vendor preset: enabled)
  Active: failed (Result: exit-code) since Mon 2018-08-13 12:22:01 UTC; 4s ago
  Process: 24577 ExecStart=/usr/local/bin/acme-dns (code=exited, status=1/FAILURE)
  Main PID: 24577 (code=exited, status=1/FAILURE)`

[LinuxCuba]

Once that worked, a permissions problem prevented reading the encryption certificates of the domain in which the daemon runs.
* acme-dns.service - Limited DNS server with RESTful HTTP API to handle ACME DNS Loaded: loaded (/etc/systemd/system/acme-dns.service; enabled; vendor preset: Active: active (running) since Mon 2018-08-13 14:32:58 UTC; 4s ago Main PID: 25024 (acme-dns) Tasks: 4 (limit: 4915) CGroup: /system.slice/acme-dns.service -25024 /usr/local/bin/acme-dns

Aug 13 14:32:58 certbot systemd[1]: acme-dns.service: Failed to reset devices.li
Aug 13 14:32:58 certbot systemd[1]: Started Limited DNS server with RESTful HTTP
Aug 13 14:32:59 certbot acme-dns[25024]: time="2018-08-13T14:32:58Z" level=info
Aug 13 14:32:59 certbot acme-dns[25024]: time="2018-08-13T14:32:58Z" level=debug
Aug 13 14:32:59 certbot acme-dns[25024]: time="2018-08-13T14:32:58Z" level=debug
Aug 13 14:32:59 certbot acme-dns[25024]: time="2018-08-13T14:32:58Z" level=debug
Aug 13 14:32:59 certbot acme-dns[25024]: time="2018-08-13T14:32:58Z" level=debug
Aug 13 14:32:59 certbot acme-dns[25024]: time="2018-08-13T14:32:58Z" level=debug
Aug 13 14:32:59 certbot acme-dns[25024]: time="2018-08-13T14:32:58Z" level=info
Aug 13 14:32:59 certbot acme-dns[25024]: time="2018-08-13T14:32:58Z" level=inf`

[LinuxCuba]

Despite being working, why this error?
systemd[1]: acme-dns.service: Failed to reset devices.list