service discovery for broker

tests/automatic/full_chain/simple_chain/check_windows.bat

tests/automatic/settings/discovery_settings.json.tpl

...s/automatic/worker/next_multithread_broker/CMakeLists.txt

...s/automatic/worker/next_multithread_broker/check_linux.sh

...utomatic/worker/next_multithread_broker/check_windows.bat

tests/manual/performance_broker/discovery.json

tests/manual/performance_full_chain_simple/discovery.json

tests/manual/performance_full_chain_simple/fluentd.conf

tests/manual/performance_full_chain_simple/test.sh

worker/api/cpp/include/worker/data_broker.h

worker/api/cpp/src/server_data_broker.cpp

worker/api/cpp/src/server_data_broker.h

worker/api/cpp/unittests/test_server_broker.cpp