Common class of all of the named objects in the XML Schema model.
Because 'being named' is not part of the XML Schema logical
object hierarchy, this is used as a delegate, not as a base class.
By definition, all of these objects live in some particular (parent)
The parent is intentionally immutable; there's no good reason to move
an object from one schema to another, and this simplifies some of the
Get the QName for this object. This is always the formal name that identifies this
item in the schema. If the item has a form (an element or attribute), and the form
is 'unqualified', this is not the appropriate QName in an instance
document. For those items, the getWiredName method returns the appropriate
QName for an instance document.