Extenions: Drop virtual inheritance

Due to problems onthe windows platform the virtual inheritance approach must be dropped. NExt to the already reimplemented proeprty interface the Type interface is reimplemented too. This change allows to revert some earlier changes.

src/App/PropertyContainer.cpp

@@ -51,6 +51,7 @@ TYPESYSTEM_SOURCE(App::PropertyContainer,Base::Persistence);
 // here the implemataion! description should take place in the header file!
 PropertyContainer::PropertyContainer()
 {
+    propertyData.parentPropertyData = 0; 
 }
 
 PropertyContainer::~PropertyContainer()