Saves the colour table for the currently open graphics device KPG1_LTSAV
"
kappa_lut.sdf"
and contains LUTs for different devices.
Each LUT is a _REAL array of shape (3,n) where n is the number of colours in the LUT. Each array has
a name which identifies the graphics device to which it refers. The HDS container file is created if it does not already exist.
A graphics device must previously have been opened using PGPLOT.