Non backward compatible change of XStream data format

Issue

• In JBoss Fuse 6.3 XStream data format now uses default security as per AbstractXStreamWrapper.

private static final String PERMISSIONS_PROPERTY_DEFAULT = "-*,java.lang.*,java.util.*";

• This disallows all classes except java.lang,java.util to be serialised.
• 6.3 Migration guide does not mention about this.