Schrievkrom

After a long time some work to do for PUM – fixing some problems:

• shadowing classes could not be deleted. If you want to delete an API class the system initially checked, if there is a shadowed classes (in the domain hierarchy). This check is not correct. The other was round the check is ok (if you want to delete a domain class)
• some meta attributes changes of a domain class attribute were not copied to API classes.
• if one deletes an attribute in the domain class hierarchy the attributes (with the same name) in that shadowed API class hierarchy should also be deleted.