Sets the z-value for this layer to the inputed value.
        
        :param      zValue | <int>
        
        :return     <bool> changed

def setZValue(self, zValue):
        """
        Sets the z-value for this layer to the inputed value.
        
        :param      zValue | <int>
        
        :return     <bool> changed
        """
        if zValue == self._zValue:
            return False
        
        self._zValue = zValue
        self.sync()
        return True