BC break in QMacCocoaViewContainer / QMacNativeWidget

Some method signatures changed:

• QMacCocoaViewContainer(void *cocoaViewToWrap, QWidget *parent = 0);
  + QMacCocoaViewContainer(NSView *cocoaViewToWrap, QWidget *parent = 0);
  virtual ~QMacCocoaViewContainer();

• void setCocoaView(void *cocoaViewToWrap);
• void *cocoaView() const;
  + void setCocoaView(NSView *view);
  + NSView *cocoaView() const;

• QMacNativeWidget(void *parentRef = 0);
  + QMacNativeWidget(NSView *parentView = 0);