[PyQt] QML non-NOTIFYABLE property warning on Person example.

[bootch at nc.rr.com]

I get some such warning from QML engine when I do something like: "MenuItem { enabled: person.shoe " where Person is defined on the Python side and registered per the example in the PyQt documentation.  (I want a menu item enabled according to the value of the shoe property, supposing shoe was bool.) Is that something I can fix using the notify=signal parameter to pyqtProperty?  The PyQt documentation says "notify – the optional unbound notify signal. It is ignored by Python"  I interpret that to mean that Python doesn't care, but that it will have an effect on Qt and QML?  No big deal,  easy enough to test it, or work around.  The inner workings are just mysterious to me, QML will automagically connect that signal from the instance of person to some slot on the instance of menu item?