1.x Maintenance

Issues selected in an upcoming maintenance release of 1.x branch

• XSTR-729 2013-03-14T10-55 21/Mar/13 Turn Xstream an OSGi citizien
• XSTR-457 2007-12-13T18-57 20/Mar/13 Don't write 'defined-in' attribute if not needed
• XSTR-722 2013-02-26T14-14 19/Mar/13 ReflectionProvider.getFieldOrNull