Things like Guest.Seclabel, VirtualDevice.VirtualAlias, etc.
Now we don't need to track a full xpath with each class, just its root
name and we build its hierarchy depending on its parent.
We already had this open coded in several classes with varying methods.
Now all someone has to do is
features = XMLChildProperty(CPUFeature)
The xmlbuilder code will pull the relevant xpath from the CPUFeature class,
handling parsing into instances of that class directly. The only
thing that needs to be manually added is the add_* remove_* functions.
Cole Robinson