click on waterfall sometime does not produce the correct frequency

When XTWaterfallView:: -(void)mouseUp: (NSEvent *)theEvent
executes after zooming waterfall we get the same value for self.bounds; hence the same offset in freq will occur when zoomed as when not zoomed.

The code wasn't properly updated when I implemented the zoom
function. The coordinates need to be translated from the
CAScrollLayer that's sitting in the XTWaterfallView. A similar
operation is done in the XTPanadapterView, I just haven't gotten to
pushing the changes to XTWaterfallView yet.

This may not be the correct way but if I divide by zoomFactor it seems to fix the problem.

transceiverController.frequency += (clickPoint.x - NSMidX(self.bounds)) * hzPerUnit / zoomFactor;