more work at aai

common/cpp/include/common/networking.h

producer/api/src/producer_impl.cpp

producer/api/src/request.h

producer/api/src/request_handler_filesystem.cpp

producer/api/src/request_handler_tcp.cpp

producer/api/src/request_handler_tcp.h

producer/api/unittests/test_producer_impl.cpp

producer/api/unittests/test_request_handler_filesystem.cpp

producer/api/unittests/test_request_handler_tcp.cpp

producer/api/unittests/test_request_pool.cpp