fixed rebase

merged branch

[#887,!572] rebased

[#887,!572] updated doxygen

[#887,!572] implement mysql thread handle

[#886, !508] renamed class and moved sources

removed duplicate entry

[#883, !506] fixed rebase

[#886, !508] added unit tests

[#886, !508] added thread resource mgr

[#883, !506] updated copyrights

[#883, !506] fixed rebase

[#883, !506] fixed rebase

[#883, !506] use nullptr for empty task

[#883, !506] use references instead of objects whenever possible

[#883, !506] fixed typo

[#883, !506] fixed comments

[#883, !506] fixed comments

[#883, !506] fixed typos

[#883, !506] fixed typo

[#883, !506] fixed typo

[#883, !506] updated unit tests

[#883, !506] updated thread pool unit tests

[#883, !506] added thread pool unit tests

[#883, !506] added LockGuard unit tests

[#883, !506] added doxigen and cleaned up code

changed log messages

use std::lock_guard whenever possible

added lock guard

minor changes

clean up code

fixed unittests

support reconfigure

use blocking statistics

use nonblocking statistics

use std::lock_guard whenever possible

updated copyrights

removed copyrights

clean up code

updated multi-thread packet processing

use blocking statistics

use nonblocking statistics

use thread_local

use std::lock_guard whenever possible

updated copyrights

removed copyrights

clean up code

minor changes

fixed compilation

small changes

updated multi-thread packet processing

[#887,!572] use thread_local instead of ThreadResource

[#887,!572] rebased

[#887,!572] fixed comments

[#887,!572] clean up code

[#887,!572] updated doxygen

[#887,!572] implement mysql thread handle

[#888,!573] use thread_local instead of ThreadResource

[#888,!573] rebased

[#888,!573] clean up code

[#888,!573] updated doxygen

[#888,!573] implement pgsql thread handle

[#886, !508] fixed header

[#886, !508] removed spaces

[#886, !508] renamed class and moved sources

[#886, !508] fixed unit test

[#886, !508] clean up

[#886, !508] added unit tests

[#886, !508] added thread resource mgr

[#884,!567] use thread_local when creating exchanges

[#884,!567] removed thread_local

[#884,!567] fixed unittests

[#884,!567] use thread_local when creating exchanges

[#885,!570] use thread_local when creating exchanges

[#885,!570] removed thread_local

[#885,!570] use thread_local when creating exchanges

[#964,!577] Two trivial fixes as a result of second review.

- Addeed asterisk in the changelog to mark it incompatible change.
- Fixed comma character in the new line.

[#964,!577] Fixed segfaulting unit test

src/lib/http/client.cc
    HttpClient::CloseIfOutOfBandwith() - added missing loop
    break after erasure.

[#964,!577] Added unit tests

src/lib/dhcp/tests/iface_mgr_unittest.cc
    Modified tests to verify that external socket callbacks receive
    the correct socket descriptor when invoked by IfaceMgr.

src/lib/http/tests/server_client_unittests.cc
    TEST_F(HttpClientTest, closeIfOutOfBandwidth) - new test to
    verifies HttpClient::closeIfOutOfBandwidth()

[#964,!577] Revamped to detect and close OOB Connections

Rather than just unregistering the socket, we now actually close
the Connection. This ensures we never end up with an unregistered
but open connection.

src/hooks/dhcp/high_availability/ha_service.*
    HAService::clientConnectHandler() - modified to call
    HttpClient::closeIfOutOfBandwidth().

src/lib/http/client.*
    Connection - replaced isTransaction(int socket_fd) with
    isMySocket(int socket_fd)

    ConnectionPool - replaced isTransaction(int socket_fd) with
    closeIfOutOfBandwidth(int socket_fd)

    HttpClient - replaced isTransaction(int socket_fd) with
    closeIfOutOfBandwidth(int socket_fd)

[#964,!577] Added external socket ready handler to HAService

src/hooks/dhcp/high_availability/ha_service.*
    HAService::socketReadyHandler(int tcp_native_fd) - new handler for external socket ready
    callback. It detects out-of-transaction ready socket and unregisters it.

src/lib/http/client.*
    isTransactionOngoing(int socket_fd) - new method to return true if any of the clients
    connections are using the socket in an ongoing transaction

[#964,!577] Added socket descriptor parameter to IfaceMgr external callback handler

src/lib/dhcp/iface_mgr.*
    typedef SocketCallback - added socket descriptpor parameter
    Added socket fd to invocations of socket ready callback

src/bin/dhcp4/dhcp4to6_ipc.*
    void Dhcp4to6Ipc::handler(int /* fd */)

src/bin/dhcp6/dhcp6to4_ipc.*
    void Dhcp6to4Ipc::handler(int /* fd */)

     Dhcp6to4Ipc& ipc = Dhcp6to4Ipc::instance();
     Pkt6Ptr pkt;

src/hooks/dhcp/high_availability/ha_service.*
    socketReadyHandler() - initial stub implementation of socket ready handler

[970-implement-multi-threading-critical-section] Removed the enabled_ local copy of the MT mode

[970-implement-multi-threading-critical-section] Moved to Camel names

[970-implement-multi-threading-critical-section] Finished first version

[970-implement-multi-threading-critical-section] First version

[#989] updated version and fixed some typos

[#974] slightly changed documentation about netconf

Merge branch '974-1-7-1-release' of https://gitlab.isc.org/isc-projects/kea into 974-1-7-1-release

[#974] parsers regenerated for 1.7.1

[#974] copy right dates, mes files Changelog prepared for release

[#971] copy right dates, mes files Changelog prepared for release

[#971] bumped up lib versions for 1.7.1

[fix-904-2] Fixed rebase failures

[fix-904] Removed extra argument

[904-add-ability-to-force-a-cb-update-remotely] Fixed typo

[904-add-ability-to-force-a-cb-update-remotely] Updated Changelog entry

[904-add-ability-to-force-a-cb-update-remotely] Used "on demand" instead of pull at the exception of the command name

[904-add-ability-to-force-a-cb-update-remotely] Added ChangeLog entry for config-backend-pull

[904-add-ability-to-force-a-cb-update-remotely] Addressed last comments