Kpi value api in progress

proto/kpi_value_api.proto

src/common/Constants.py

src/common/tools/kafka/Variables.py

src/kpi_manager/service/KpiManagerService.py

src/kpi_manager/tests/test_kpi_manager.py

src/kpi_value_api/__init__.py

src/kpi_value_api/client/KpiValueApiClient.py

src/kpi_value_api/client/__init__.py

src/kpi_value_api/service/KpiValueApiService.py

src/kpi_value_api/service/KpiValueApiServiceServicerImpl.py

src/kpi_value_api/service/NameMapping.py

src/kpi_value_api/service/__init__.py

src/kpi_value_api/tests/messages.py

src/kpi_value_api/tests/test_kpi_value_api.py