[868-the-examples-directory-in-main-dir-not-doc-examples-is-useless-and-should-be-removed] Removes topdir examples

This reverts commit 9c1ab213.

src/lib/dhcpsrv/alloc_engine.cc
    AllocEngine::allocateLeases6(ClientContext6& ctx) - add call to
    updateLeaseData() to case 3.

src/lib/dhcpsrv/tests/alloc_engine6_unittest.cc
    TEST_F(AllocEngine6Test, hostDynamicAddress)
    TEST_F(AllocEngine6Test, globalHostDynamicAddress) - revamped to
    verify assignment and update for REQUESTs

[392-search-of-reservations-by-hostname] Added a reference in reservation-get-by-hostname to admin/MySQL

src/lib/dhcpsrv/parsers/simple_parser4.cc
src/lib/dhcpsrv/parsers/simple_parser6.cc
    Fixed indentations in defaults list

Addressed a myriad of minor typos and wording issues.

modified:
ChangeLog
doc/examples/kea4/all-keys.json
doc/examples/kea6/all-keys.json
doc/sphinx/arm/dhcp4-srv.rst
doc/sphinx/arm/dhcp6-srv.rst
src/bin/dhcp4/dhcp4_srv.cc
src/bin/dhcp4/tests/config_parser_unittest.cc
src/bin/dhcp4/tests/fqdn_unittest.cc
src/bin/dhcp6/tests/config_parser_unittest.cc
src/bin/dhcp6/tests/d2_unittest.cc
src/bin/dhcp6/tests/fqdn_unittest.cc
src/lib/dhcpsrv/alloc_engine.cc
src/lib/dhcpsrv/alloc_engine.h
src/lib/dhcpsrv/d2_client_cfg.h
src/lib/dhcpsrv/parsers/base_network_parser.cc
src/lib/dhcpsrv/srv_config.h

Updated:
    doc/examples/kea4/all-keys.json
    doc/examples/kea4/with-ddns.json
    doc/examples/kea6/all-keys.json
    doc/sphinx/arm/dhcp4-srv.rst
    doc/sphinx/arm/dhcp6-srv.rst

Added ChangeLogEntry

src/bin/dhcp4/tests/get_config_unittest.cc
src/bin/dhcp6/tests/get_config_unittest.cc
    regenerated tests

src/lib/dhcpsrv/parsers/simple_parser4.cc
    Removed DDNS params from INHERIT_TO_SUBNET4 list

src/lib/dhcpsrv/parsers/simple_parser6.cc
    Removed DDNS params from INHERIT_TO_SUBNET6 list

src/bin/dhcp6/tests/fqdn_unittest.cc
    TEST_F(FqdnDhcpv6SrvTest, ddnsScopeTest)  - new test

src/bin/dhcp6/ctrl_dhcp6_srv.cc
    Removed setting D2ClientCfg fetch function

src/bin/dhcp6/dhcp6_lexer.ll
src/bin/dhcp6/dhcp6_parser.yy
    ddns-send-updates
    ddns-override-no-update
    ddns-override-client-update
    ddns-replace-client-name
    ddns-generated-prefix
    ddns-qualifying-suffix
    - added to DHCP4,SHARED_NETWORK,SUBNET4

    hostname-char-set
    hostname-char-replacement
    - added to SHARED_NETWORK,SUBNET4

src/bin/dhcp6/dhcp6_srv.cc
    Dhcpv6Srv::processClientFqdn()
    Dhcpv6Srv::createNameChangeRequests()
    Dhcpv6Srv::updateReservedFqdn()
    - use cxt.getDdnsParams()

src/bin/dhcp6/json_config_parser.cc
    configureDhcp6Server()
    - use SrvConfig::moveDdnsParams() to move dhcp-ddns parameters
    - handle new "ddns-" globals

src/bin/dhcp6/tests/config_parser_unittest.cc
src/bin/dhcp6/tests/fqdn_unittest.cc
src/bin/dhcp6/tests/get_config_unittest.cc
    Updated tests

src/bin/dhcp4/ctrl_dhcp4_srv.cc
    Removed setting D2ClientCfg fetch function

src/bin/dhcp4/dhcp4_lexer.ll
src/bin/dhcp4/dhcp4_parser.yy
    ddns-send-updates
    ddns-override-no-update
    ddns-override-client-update
    ddns-replace-client-name
    ddns-generated-prefix
    ddns-qualifying-suffix
        - added to DHCP4,SHARED_NETWORK,SUBNET4

    hostname-char-set
    hostname-char-replacement
        - added to SHARED_NETWORK,SUBNET4

src/bin/dhcp4/dhcp4_srv.cc

    Dhcpv4Srv::processClientFqdnOption()
    Dhcpv4Srv::processHostnameOption()
    Dhcpv4Srv::assignLease()
        Use scoped DdnsParams from context to make decisions, pass
        into D2ClientMgr functions, and supply hostname sanitizer

src/bin/dhcp4/json_config_parser.cc
    configureDhcp4Server()
    - use SrvConfig::moveDdnsParams() to move dhcp-ddns parameters
    - handle new "ddns-" globals

src/bin/dhcp4/tests/config_parser_unittest.cc
src/bin/dhcp4/tests/d2_unittest.cc
src/bin/dhcp4/tests/dhcp4_test_utils.cc
src/bin/dhcp4/tests/fqdn_unittest.cc
src/bin/dhcp4/tests/get_config_unittest.cc
    Updated and new tests

src/lib/dhcpsrv/alloc_engine.*
    AllocEngine::ClientContext6::getDdnsParams()
    AllocEngine::ClientContext4::getDdnsParams() - new
    methods which return a DdnsParams instance scoped by
    currently selected subnet

    Replaced direct references to context::ddns_params_ with
    new getter methods.

src/lib/dhcpsrv/parsers/simple_parser4.cc
src/lib/dhcpsrv/parsers/simple_parser6.cc
    Removed global defaults for hostname-char-set/replacement

Moving the parameters needs to be done before defaults are applied to the
config, so moveDdnsParams was changed to modify a mutable top level
element map instead of SrvConfig contents.

src/lib/dhcpsrv/parsers/simple_parser4.cc
src/lib/dhcpsrv/parsers/simple_parser6.cc
    Change ddns-send-updates default to true.

src/lib/dhcpsrv/srv_config.*
    SrvConfig::getConfiguredGlobal() - new method to fetch a
    global by name

    SrvConfig::moveDdnsParams() - changed to accept/modify
    a top-level Element map

src/lib/dhcpsrv/tests/srv_config_unittest.cc
    updated unit tests accordingly

src/lib/dhcpsrv/dhcpsrv_messages.*
    DHCPSRV_CFGMGR_DDNS_PARAMETER_IGNORED
    DHCPSRV_CFGMGR_DDNS_PARAMETER_MOVED

src/lib/dhcpsrv/srv_config.*
    SrvConfig::moveDdnsParams() - new method to move
    parameters from dhcp-ddns to configured globals.

src/lib/dhcpsrv/tests/srv_config_unittest.cc
    TEST_F(SrvConfigTest, moveDdnsParamsTest) - new test

src/lib/dhcpsrv/d2_client_cfg.*
    Added hostname-char-set and hostname-char-replacement to DdnsParms
    DdnsParams::getHostnameSanitizer()  - new function to return a sanitizer

src/lib/dhcpsrv/d2_client_mgr.h
    D2ClientMgr::adjustDomainName() - now gets sanitizer from ddns_params

src/lib/dhcpsrv/network.*
src/lib/dhcpsrv/parsers/base_network_parser.cc
src/lib/dhcpsrv/parsers/simple_parser4.cc
src/lib/dhcpsrv/parsers/simple_parser6.cc
    Added hostname-char-set and hostname-char-replacement to networks and subnets