Reviewed required a few comments to be added.

Replaced logic in Dhcpv6Srv::generateFqdn() which constructed the
FQDN from the lease address to use D2ClientMgr::generateFqdn() method.
Removed remaining obsolete FQDN_ constants.

Dhcpv6Srv now uses method in CfgMgr to test whether or not ddns updates
are enabled.  Add unit tests to verify NCRs are or are not created
accordingly.

Replaced constants and logic in Dhcp6Srv::processClientFqdn()
with use of D2ClientMgr configuration-sensitive FQDN flag
and domain name methods.

Added "dhpc-ddns" element to dhcp6.spec file.
Added "dhcp-ddns" to list of elements recognized in createGlobal6DhcpConfigParser()
Added unit tests for dhcp-ddns parsing.

Conflicts:
	src/lib/datasrc/database.cc

valgrind reported an invalid D2ClientMgr is destroyed while in send mode
Added call to stopSender to D2ClientMgr destructor.

Unit test was failing as a closed fd passed to select() does not fail
on all OSs.  Changed the test so it verifies that the fd in question
no longer evaluates to ready to ready.

Integrates use of NameChangeUDPSender in D2ClientMgr.

Conflicts:
	ChangeLog

Conflicts:
	ChangeLog
	src/bin/dhcp4/dhcp4_srv.cc
	src/bin/dhcp4/tests/dhcp4_srv_unittest.cc
	src/bin/dhcp4/tests/dhcp4_test_utils.h
	src/lib/dhcpsrv/cfgmgr.cc
	src/lib/dhcpsrv/cfgmgr.h

Master updated while merging in 3299.

Also ran dhcp_ddns_messages.mes through reorder tool.

This prevents errors reported by valgrind about uninitialized value of
hops being used in unit tests which skip parsing the packet. Okayed
on jabber.

b10-dhcp-ddns uses lease length as TTL in DNS update RRsets.

Shored up the error handling in the sender when the WatchSocket fails to mark
or clear. Addes unit tests accordingly.

 - getRelayInfo() implemented, relay_ is now protected
 - setRelay => setRelayInfo
 - Option::Universe is passed as const reference
 - Further clarified white_list_ field in Subnet.h

Conflicts:
	src/bin/dhcp4/tests/fqdn_unittest.cc

Fixed a couple doxgyen errors and removed the commented
out include of ioctl.h in d2_upd_unittest.cc

Made behavior of dhcp_ddns::WatchSocket a bit more robust in handling
programmatic abuse.
Cleaned up addresses used in ncr_upd_unittest.cc, added specific test
for client side address if 0.0.0.0/port 0.
Updated copyrights as appropriate and other cosmetics.

 - RelayInfoParser now takes Option::Universe as last parameter;
 - Extra tests for checking invalid parameters in RelayInfoParser
 - Comments in subnet.h improved
 - Sanity checks in RelayInfoParser implemented, doc improved

Also added a pointer to valid message types on IANA website, in the log
message description.

 - Copyright years updated
 - Minor corrections in BINDX Guide
 - dhcp4.spec relay structure description updated.
 - new unit-test for DHCPv4 client classification added
 - new unit-test for DHCPv6 client classification added
 - fixed Doxygen errors
 - comments for CfgMgr::getSubnet{4,6} updated

Changed build request methods in d2::NameAddTransaction to set the RRset TTL
value to the value of NameChangeRequest::lease_length.