actual behaviour

QmitkNodeDescriptor* QmitkNodeDescriptorManager::GetDescriptor( const QString& _ClassName ) const returns NULL if "Unknown" is passed

expected behaviour

method should return the UnknownDataNodeDescriptor, which handles all unknown DataNodeTypes

cause of the bug

UnknownDataNodeDescriptor is not in the list of nodedescriptors but rather a standalone member

solution

return UnknownDataNodeDescriptor if "Unknown" is passed as parameter in GetDescriptor(), otherwise proceed as usual

testing

manual testing/trivial change