a) Conversion RealToInteger:  fixed the reuslting DICOM header, so the NumberOfBits\HighBit etc match the ones specified by the User.

b)  Threshold to ROI:  resulting ROI DiCOM header has now NumberOfBits=1

"ThresholdToRoi by Signal interval":  fixed the defect when specified interval was partially outside the range present in the image.
Provided an info message when the result of the operation is an empty ROI.