nsd: 4.1.7 -> 4.1.9

[hrdinka]

Things done

• Tested using sandboxing
  (nix.useSandbox on NixOS,
  or option build-use-sandbox in nix.conf
  on non-NixOS)
• Built on platform(s)
  • NixOS
  • OS X
  • Linux
• Tested compilation of all pkgs that depend on this change using nix-shell -p nox --run "nox-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Fits CONTRIBUTING.md.

---

Features

• Fix Build haddock for transformers-compat #732: tcp-mss, outgoing-tcp-mss options for nsd.conf, patch from Daisuke Higashi.
• Fix meta.license and meta.licenses standardisation #739: zonefile changes when mtime is small are detected on reload, if filesystem supports precision mtime values.
• RR type CSYNC (RFC7477) syntax is supported.

Bugfixes

• Change the nsd.db file version because of nanosecond precision fix.
• take advantage of arc4random_uniform if available, patch from Loganaden Velvindron.
• Fix flto check for OSX clang.
• Define _DEFAULT_SOURCE with _BSD_SOURCE for glibc 2.20 on Linux.
• Fix Add easyrsa #736: segfault during zone transfer.
• Fix sdcv: fix build on darwin #744: Fix that NSD replies for configured but unloaded zone with SERVFAIL, not REFUSED.

[mention-bot]

By analyzing the blame information on this pull request, we identified @aszlig and @vcunat to be potential reviewers