code: func typeName(att *design.AttributeDefinition) (name string) {
  	if ut, ok := att.Type.(*design.UserTypeDefinition); ok {
  		name = Goify(ut.TypeName, true)
  	} else if mt, ok := att.Type.(*design.MediaTypeDefinition); ok {
  		name = Goify(mt.TypeName, true)
  	}
  	return
  }
docs: // typeName returns the type name of the given attribute if it is a named type, empty string otherwise.