Added the -s option to define the co-ordinate system of the derived velocities. Ensured that the plots of spectra use the axis co-ordinate system. The script inquires the WCS for the rest-frame frequency to avoid unnecessary prompting.
Changed lower percentile for display from 15 to 2. Use spectrum colour table. Added a velocity key.
Additional -c option to specify the number of contours; this may be zero to prevent contours be overlaid. Added -ci option to specify the colour index of contours.
DATACUBE --- An IFS datacube manipulation package