bugfix: saving display settings works fine now

.../client/application/framework/DisplaySettingsManager.java

.../client/application/framework/IDisplaySettingsGetter.java

...t/web/client/application/ui/grid/AbstractBrowserGrid.java

.../client/application/ui/grid/ColumnSettingsConfigurer.java

...generic/client/web/client/dto/DefaultResultSetConfig.java

...enbis/generic/client/web/client/dto/IResultSetConfig.java

...is/generic/client/web/client/dto/TableExportCriteria.java

...c/client/web/server/resultset/CachedResultSetManager.java

...temsx/cisd/openbis/generic/shared/basic/dto/SortInfo.java

...ic/client/web/clientnonjs/DisplaySettingsManagerTest.java

...ient/web/server/resultset/CachedResultSetManagerTest.java

...ch/systemsx/cisd/openbis/systemtest/FilterSystemTest.java