Encrypted NTS time servers for datetime plugin

Hi there,

I was wondering if it wouldn't make sense to stop using the ntpdate package for the datetime plugin. I have read that ntpdate has been deprecated for some time and is no longer available or has been merged into the ntp package.

In general, the use of ntpdate has long been discouraged. It would probably only be justified for a one-time time query during boot.

I also find the following excerpt from the IBM documentation quite interesting: "However, it is important to note that ntpdate with contrived cron scripts is not a substitute for the NTP daemon, which uses complex algorithms to maximize accuracy and reliability while minimizing resource use. Finally, since ntpdate does not tune the host clock frequency as does ntpd, the accuracy using ntpdate is limited."

In addition, neither ntp nor ntpdate supports the use of an encrypted time server according to NTS. So it might be a good idea to switch to chrony. Chrony is now very proven, stable and widely used, and it looks like chrony is the future.