-BUGFIX: changing an Class Icon will now immediately
-BUGFIX: the new class dialog takes now care about the heir
-FEATURE: Added drag& drop to the ObjectTree.
-FEATURE: Added drag& drop to the ClassTree.
-FEATURE: It is now possible to link an object.
-FEATURE: The ObjectTree is was completely overhauled.
-FEATURE: The ClassTree is was completely overhauled.
-FEATURE: Added an WelcomeDialog.
-FEATURE: Its now posible to configure the Vaild parents for classes.