start working on stream infos, refactoring

CHANGELOG.md

broker/src/asapo_broker/database/mongodb.go

broker/src/asapo_broker/database/mongodb_test.go

common/cpp/include/asapo/common/data_structs.h

common/cpp/src/data_structs/data_structs.cpp

common/cpp/unittests/data_structs/test_data_structs.cpp

consumer/api/cpp/include/asapo/consumer/consumer.h

consumer/api/cpp/src/consumer_impl.cpp

consumer/api/cpp/src/consumer_impl.h

consumer/api/cpp/unittests/test_consumer_impl.cpp

consumer/api/python/asapo_consumer.pxd

consumer/api/python/asapo_consumer.pyx.in

producer/api/cpp/src/producer_impl.cpp

producer/api/python/asapo_producer.pxd

producer/api/python/asapo_producer.pyx.in

...er/src/request_handler/request_handler_db_last_stream.cpp

...er/src/request_handler/request_handler_db_stream_info.cpp

tests/automatic/consumer/consumer_api/check_linux.sh

tests/automatic/consumer/consumer_api/consumer_api.cpp