Implement syslog protocol to send event log to syslog server.

[rtrbt]

https://www.tinkerunity.org/topic/7788-externes-syslog
https://en.wikipedia.org/wiki/Syslog
https://www.rfc-editor.org/rfc/rfc5424.html

[kai-uwe-rommel]

Will be important if someone installs a significant number of wallboxes and wants to manage these centrally.