CUPID now creates STC-S polygons

I've added an option to CUPID:FINDCLUMPS to allow it to create an STC-S description (either polygonal or elliptical) for each clump it finds, and add them into the output clump catalogue. I've also modified KAPPA:LISTSHOW so that it can display the STC-S shapes over a displayed image. Below is an example. In the first image, the greyscale (and contours) are the data, and the red lines are the polygonal clump outlines. They overlap slightly in some cases because each polygon is only allowed to have up to 15 vertices, and so only approximates the clump pixel mask.



The next image is the corresponding pixel mask (each colour represents the pixels assigned to a single clump).