return nacks

broker/src/asapo_broker/database/mongodb.go

broker/src/asapo_broker/database/mongodb_test.go

broker/src/asapo_broker/server/get_nacks.go

broker/src/asapo_broker/server/get_nacks_test.go

broker/src/asapo_broker/server/listroutes.go

common/cpp/include/common/data_structs.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