incomplete datasets for consumer

CHANGELOG.md

common/cpp/include/common/data_structs.h

common/cpp/src/data_structs/data_structs.cpp

consumer/api/cpp/include/consumer/consumer_error.h

consumer/api/cpp/include/consumer/data_broker.h

consumer/api/cpp/src/server_data_broker.cpp

consumer/api/cpp/src/server_data_broker.h

consumer/api/cpp/unittests/test_server_broker.cpp

consumer/api/python/asapo_consumer.pxd

consumer/api/python/asapo_consumer.pyx.in