Use per-provider configuration `min-interval` (via `wait-time` config) to control IP address update interval instead of modifying the global `daemon` property to slow everything down. Controlling `daemon` has a few side effects:
- Installations using services like `sit` tunnels (e.g. tunnelbroker.net) might have an impact
- `daemon` configuration in `ddclient` also controls the actual Perl service that stays resident in the system. We ought to move to systemd timer anyway and avoid keeping the Perl process resident
- The slowing down the daemon doesn't serve the original intention anyway. `ddclient` would hit a provider multiple times even in single-pass because of incorrect cache data (see T5573)
While at this, also support per configuration `max-interval` (via `expiry-time` config) for completeness.