fix: warnings of Eclipse 3.5

.../client/web/client/application/model/BaseEntityModel.java

...client/application/ui/file/AttachmentFileUploadField.java

...c/client/web/client/application/util/lang/IntHashMap.java

...s/generic/client/web/server/translator/DtoConverters.java

...eneric/server/authorization/DefaultReturnValueFilter.java

...eneric/shared/authorization/predicate/ArrayPredicate.java

...c/shared/authorization/predicate/CollectionPredicate.java

.../systemsx/cisd/openbis/generic/shared/basic/dto/Code.java

...msx/cisd/openbis/generic/shared/basic/dto/Identifier.java

...ava/ch/systemsx/cisd/openbis/generic/shared/dto/Code.java

...emsx/cisd/openbis/generic/shared/util/HibernateUtils.java

...tion/ui/property_type/FillPropertyTypeAssignmentForm.java

...s/generic/server/authorization/PredicateExecutorTest.java

...client/application/experiment/FillExperimentEditForm.java

...pplication/experiment/FillExperimentRegistrationForm.java

...client/application/sample/FillSampleRegistrationForm.java

...eb/client/application/sample/GenericSampleViewerTest.java