#26 Dicom preview reformats gray incorrectly

[Ofri Sadowsky]

The Dicom preview window (Slicer 1.3.0, Windows NT)
reformats the intensity levels incorrectly. I have a
CT scan in Hounsfield numbers (that is, including
negative as well as positive values). The preview
displays almost all the pixels as white, probably
because they are interpreted as positive 65??? instead
of negative -???.