Indicate number of clipped pixels in statistics panel.

[Alistair M]

In the Statistics panel, it would be great to know how many pixels are being clipped dark (0 adu) and how many are clipped bright (max adu).

This will help the user to determine good settings for exposure length and gain.

[Stefan B]

Min and Max pixel values will be determined in next version together with their occurrences. This implicitly tells the number of clipped pixels.