hints.use_nodata(true) by default

I believe that's what most users want; practical motivation:
https://forum.turris.cz/t/kresd-responds-to-hints-with-nxdomain-for-aaaa-requests/8353
25 jobs for <span class="ref-name">hints-use_nodata</span> in 41 minutes and 43 seconds (queued for 10 seconds)
Status Job ID Name Coverage
  Build
passed #179760
docker linux amd64
build:clang:linux:amd64

00:00:49

passed #179759
docker linux amd64
build:linux:amd64

00:00:53

passed #179761
docker linux amd64 allowed to fail
srpm

00:00:34

 
  Test
passed #179768
docker linux amd64
deckard:linux:amd64

00:01:29

passed #179773
privileged
distro:epel-7

00:01:52

passed #179772
privileged
distro:fedora-29

00:02:27

passed #179767
docker
doc

00:01:02

passed #179766
docker linux amd64
installcheck:linux:amd64

00:01:16

passed #179769
docker linux amd64
installcheck:valgrind:linux:amd64

00:01:58

passed #179763
docker
lint:c

00:02:40

failed #179764
docker allowed to fail
lint:clang-scan-build

00:01:16

passed #179762
docker
lint:lua

00:00:49

passed #179771
docker linux amd64
respdiff:iter:udp:linux:amd64

00:02:32

passed #179765
docker linux amd64
test:linux:amd64

00:01:16

passed #179770
docker linux amd64
test:linux:amd64:valgrind

00:01:22

 
  Respdiff
passed #179774
respdiff
respdiff:fwd-tls6-kresd.udp6

00:21:08

failed #179775
respdiff
respdiff:fwd-udp6-kresd.udp6

00:36:40

passed #179779
respdiff
respdiff:fwd-udp6-unbound.tcp6

00:20:08

passed #179780
respdiff
respdiff:fwd-udp6-unbound.tls6

00:17:32

passed #179778
respdiff
respdiff:fwd-udp6-unbound.udp6

00:31:10

passed #179777
respdiff
respdiff:iter.tls6

00:38:09

failed #179776
respdiff
respdiff:iter.udp6

00:29:09

passed #179781
respdiff
resperf:fwd-tls6.udp-asan

00:23:01

passed #179782
respdiff
resperf:fwd-udp6.udp-asan

00:28:01

passed #179783
respdiff
resperf:iter.udp-asan

00:32:32

 
Name Stage Failure
failed
respdiff:iter.udp6 Respdiff
~/builds/ea0ef08e/7/knot/knot-resolver
Running after script...
$ cp -t . respdiff_commitdir/$RESPDIFF_TEST/j* ||:
$ cp -t . respdiff_commitdir/*$RESPDIFF_TEST*.png ||:
Uploading artifacts...
./j*: found 9 matching files
./*.png: found 3 matching files
Uploading artifacts to coordinator... ok id=179776 responseStatus=201 Created token=GzKxkrbs
ERROR: Job failed: exit status 1
failed
respdiff:fwd-udp6-kresd.udp6 Respdiff
~/builds/ea0ef08e/5/knot/knot-resolver
Running after script...
$ cp -t . respdiff_commitdir/$RESPDIFF_TEST/j* ||:
$ cp -t . respdiff_commitdir/*$RESPDIFF_TEST*.png ||:
Uploading artifacts...
./j*: found 9 matching files
./*.png: found 3 matching files
Uploading artifacts to coordinator... ok id=179775 responseStatus=201 Created token=TSuyxH9s
ERROR: Job failed: exit status 1
failed
lint:clang-scan-build Test
  CCLD	modules/bogus_log/bogus_log.so
CCLD modules/hints/hints.so
CCLD modules/stats/stats.so
scan-build: 32 bugs found.
scan-build: Run 'scan-view /builds/knot/knot-resolver/scan-results/2018-10-04-114052-14-1' to examine bug reports.
Uploading artifacts...
scan-results: found 37 matching files
Uploading artifacts to coordinator... ok id=179764 responseStatus=201 Created token=YwKN3zVc
ERROR: Job failed: exit code 1