fix: compiler warnings

.../client/api/gui/AbstractWebStartClientServingServlet.java

...ric/client/api/gui/DataSetUploadClientServingServlet.java

.../web/client/application/model/EntityGridModelFactory.java

...client/web/client/application/ui/grid/ColumnListener.java

...web/client/application/ui/widget/SimpleModelComboBox.java

...ric/client/web/client/application/util/lang/Entities.java

...enbis/generic/client/web/server/UploadServiceServlet.java

...bis/generic/client/web/server/resultset/CacheManager.java

.../generic/client/web/server/resultset/ColumnSortUtils.java

...d/openbis/generic/server/AuthenticationServiceHolder.java

...is/generic/server/authorization/AuthorizationAdvisor.java

...neric/server/authorization/AuthorizationDataProvider.java

...isd/openbis/generic/server/dataaccess/db/AbstractDAO.java

...isd/openbis/generic/server/util/HibernateTransformer.java

...msx/cisd/openbis/generic/shared/basic/PrimitiveValue.java

...ent/web/client/testframework/PropertyCheckingManager.java

...s/generic/server/authorization/AuthorizationTestUtil.java

...ic/server/authorization/DefaultReturnValueFilterTest.java