Installation of 'systemd-timesyncd' fails on Ubuntu 18.04

[cherbst]

The message is:
No package matching 'systemd-timesyncd' is available
On Ubuntu 18.04 'systemd-timesyncd' is provided by the package 'systemd' that's why the installation fails.

[spantaleev]

My testing showed that systemd-timesyncd is not available on Ubuntu 18.04 at all, neither as a separate systemd-timesyncd package, nor as part of the main systemd package.

Because of this, I've made Ubuntu 18.04 use ntp instead.

If you think systemd-timesyncd is available on Ubuntu 18.04 somehow, let me know and we can revisit this.