SP-420 BIS-282 present feature values from the contained dataset level

...d/openbis/dss/generic/server/TabularDataGraphServlet.java

...erver/plugins/ImageAnalysisMergedRowsReportingPlugin.java

.../openbis/dss/screening/server/DssServiceRpcScreening.java

...ugin/screening/server/ScreeningBusinessObjectFactory.java

...cisd/openbis/plugin/screening/server/ScreeningServer.java

...gin/screening/server/logic/FeatureVectorValuesLoader.java

...bis/plugin/screening/server/logic/PlateContentLoader.java

...nbis/plugin/screening/server/logic/WellContentLoader.java

...n/screening/server/logic/WellFeatureCollectionLoader.java

...ugin/screening/shared/basic/dto/FeatureVectorDataset.java

.../plugin/screening/shared/imaging/FeatureVectorLoader.java

...gin/screening/shared/imaging/IHCSFeatureVectorLoader.java

...nbis/dss/screening/server/DssServiceRpcScreeningTest.java

...tion/detailviewers/heatmaps/WellTooltipGeneratorTest.java

...gin/screening/shared/imaging/FeatureVectorLoaderTest.java