(GH-77) Fix for Exception has been thrown by the target of an invocation.
(GH-77) Fix for Exception has been thrown by the target of an invocation.

The 2 new properties EnableMinimize and EnableMaxRestore are updating the Window style which causes this exception if the HWND is disposed or the root visual is not set.

Add a simple check at the property changed callbacks to avoid this exception.

punker76/Controlz,ControlzEx/ControlzEx