449487: New Extensibility Concept for Scout 

Change-Id: I1720801f774c63266515ad2b84ea04deb8b9efc8
Task-Url: https://bugs.eclipse.org/bugs/show_bug.cgi?id=449487
DTOs re-generated
Added test cases for old and new extension support working together
(@Replace and @InjectFieldTo vs. IExtensible and IExtensionRegistry)