Log Message:
Update to 4.2.0

Changelog:
4.2.0
================
FEATURES:
	- Print IP address when bind socket fails with error.
	- Fix #4249: The option hide-identity: yes stops NSD from responding
	  with the hostname for chaos class queries.  Implements the RFC4829
	  security considerations.
	- Patch to add support for TCP Fast Open, from Sara
	  Dickinson (Sinodun).
	- Patch to add support for tls service on a specified tls port,
	  from Sara Dickinson (Sinodun).
	- Use travis for build check, initial unit test and clang analysis.
BUG FIXES:
	- Fix to delete unused zparser.default_apex member.
	- Fix that the TLS handshake routine sets the correct event to
	  continue when done.
	- Fix that TLS renegotiation calls the read and write routines again
	  with the same parameters when the desired event has been satisfied.
	- Fix that TCP Fastopen has better error message and supports OSX.
	- Fix to avoid buffer alloc with global buffer in tls write handler.
	- Fix to initialize event structure when accepting TCP connection.
	- Disable TLS1.0, TLS1.1 and weak ciphers, enable
	  CIPHER_SERVER_PREFERENCE, patch from Andreas Schulze.
	- further setup ssl ctx after the keys are loaded, for ECDH.
	- TLS OCSP stapling support, enabled with tls-service-ocsp: filename,
	  patch from Andreas Schulze.
	- Fix #10: Fix memory leaks caused by duplicate rr and include
	  instructions.
	- Fix to define _OPENBSD_SOURCE to get reallocarray on NetBSD.

4.1.27
================
FEATURES:
	- Deny ANY with only one RR in response, by default.  Patch from
	  Daisuke Higashi.  The deny-any statement in nsd.conf sets ANY
	  queries over UDP to be further moved to TCP as well.
	  Also no additional section processing for type ANY, reducing
	  the response size.
	- Fix #4215: on-the-fly change of TSIG keys with patch from Igor, adds
	  nsd-control print_tsig, update_tsig, add_tsig, assoc_tsig
	  and del_tsig.  These changes are gone after reload, edit the
	  config file (or a file included from it) to make changes that
	  last after restart.
BUG FIXES:
	- Fix #4213: disable-ipv6 and dnstap compile error.
	- Fix to reduce region_log_stats if condition, this removes a
	  debug statement.
        - Fix for FreeBSD port with dnstap enabled.
	- Fix to remove unused code.
	- Fix #6: nsd-control-setup: Change validity time to a shorter
	  period (<2038).
	- Fix unused definition in header remote.h.
	- Fix #4236: IPV4_MINIMAL_RESPONSE_SIZE=1480 is slightly too big.
	- Fix #4235: IP_PMTUDISC_OMIT on IPv4/UDP sockets.
	- Fixed radtree_insert memory leak.
	- Fixed access recycled variable.