@Transactional in AspectJ mode works with CallbackPreferringPlatformTransactionManager (WebSphere) as well

Effectively, AbstractTransactionAspect got refactored into around advice, reusing former TransactionInterceptor code which now lives in slightly generalized form in TransactionAspectSupport, and using a workaround for rethrowing checked exceptions.

Issue: SPR-9268
Added "entityResolver", "classDescriptorResolver", "doctypes" and further properties to CastorMarshaller

Also deprecated CastorMarshaller's "object" property in favor of "rootObject".

Issue: SPR-8470
Removed unused XStreamUtils class; direct access to the xstream field in XStreamMarshaller
Fixed test class name
Polishing
CastorMarshaller etc