Initial sd_notify support was added in #3963, but that sent signals from
both cmdRun and cmdReload. This approach has two drawbacks:
- Reloads initiated via the API do not send signals.
- The signals are sent from different processes, which requires the
`NotifyAccess=exec` directive in the unit file.
This change moves the NotifyReloading and NotifyReadiness invocations to
Load, which address both of those drawbacks. It also adds a
complimentary NotifyStopping method which is invoked from handleStop.
All the notify methods are defined in a notify package to avoid an
import loop.
Replaces the current Caddy executable with a new one from the build server. Honors custom builds, as long as plugins are registered on the Caddy website. Requires permissions to replace current executable, of course.
This is an experimental command that may get changed or removed later.
