implemented get last in group, added tests

CHANGELOG.md

CMakeIncludes/prepare_version_tag.cmake

CMakeLists.txt

PROTOCOL-VERSIONS.md

VERSIONS.md

broker/src/asapo_broker/database/mongodb.go

broker/src/asapo_broker/database/mongodb_test.go

broker/src/asapo_broker/server/get_commands_test.go

broker/src/asapo_broker/server/get_groupedlast.go

broker/src/asapo_broker/server/listroutes.go

consumer/api/c/include/asapo/consumer_c.h

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

consumer/api/cpp/src/consumer_c_glue.cpp

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

...very/src/asapo_discovery/protocols/hard_coded_consumer.go

discovery/src/asapo_discovery/protocols/protocol_test.go