README: Add explanation of settings.ntp.time-servers

[tjkirch]

Testing done:

Rendered version looks OK.

[iliana]

"URIs" seems weird to me because I expect only domain names to work for chrony.

[tjkirch]

"URIs" seems weird to me because I expect only domain names to work for chrony.

Or IPs.

I suppose this is following the implementation in #549, which improved the accuracy of the NTP server list from "any single-line string" to a URI, and so this documents it. I assume you'd prefer a modeled type that only allows an IP or hostname, with or without an "ntp://" scheme perhaps?

[iliana]

I don't really care about how it's modeled/validated (and "URI-like" seems totally fine to me). I just think the docs should say what most folks are going to expect an NTP configuration to want (domains and/or IPs).

[tjkirch]

I just think the docs should say what most folks are going to expect an NTP configuration to want

Perhaps just "A list of NTP servers" then?

[iliana]

Sounds good to me 👍

[tjkirch]

This push simplifies the description to "A list of NTP servers ..."