- This out-of-zone check caused the whole transfer to fail. IXFR needs
   to be changed to, reverting to original master (I'd just delete the
master branch to rewind, but it is locked, but oh well)

Refs #102

- Server would refuse SOA records this way and transfers would fail.

Refs #102, fixes Coverity #1049750

Refs #102

refs #102

fixes #99

Both do not interrupt any I/O, just change thread state.
This is because it is not required in most cases unless you use
infinite timeouts in I/O ops.

refs #91

refs #91

Because it was used also for thread wakeup when it isn't needed,
the only limitation is not to use infinite poll loops.
Before it was removed, it broke perfectly good transfers with EINTR.

refs #91

Like example.com..zone

This makes partial-closed connections discovery faster than waiting
full interval for the watchdog sweep.

refs #91

Reverted to usual recvmmsg/sendmmsg availability check.

refs #82

fixes #82

Treated as hostname otherwise.

- Nighlty tests would sometimes crash, when zones were not bootstrapper properly.

Also some log messages cleanup.

Also CID#1047013

refs #71, #65