* Improve source selection
* Handle offline sources as unreachable
* Open NTP server port only when necessary (client access is allowed by
- allow directive/command, peer or broadcast is configured)
+ allow directive/command or peer/broadcast is configured)
* Change default bindcmdaddress to loopback address
* Change default maxdelay to 3 seconds
* Change default stratumweight to 0.001
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* Add sanity checks for time and frequency offset
* Don't report synchronised status during leap second
+* Don't combine reference clocks with close NTP sources
* Fix accepting requests from configured sources
* Fix initial fallback drift setting