@Retention(value=RUNTIME)
 @Target(value=FIELD)
public @interface EntityMergeField
This annotation signals that a field is merged
 when using the EntityMergeService.
 
 defaultMerge() signals if a field is to be merged 
 automatically. If set to false it need to be handled
 in the mergeSpecialFields() method. 
 
 toClone() signals if the value is to be cloned 
 using the EntityClonerService while merging
 automatically. 
 
 Basic Java types can usually be merged automatically
 and don't need to be cloned.