Remix: Filament Spool Holder

For yet unknown reason did the original file not print well: OpenSCAD rendered the file ok, slic3r made a gcode file from it, but that file only printed a part of the thing.
I then reviewed the script, did some factoring and other minor changes, mostly meant to improve readability - and to my surprise, the reviewed version printed out well. As far as I can judge did I not have made any functional changes to it. Well, it has been uploaded here mainly to give the original author a way to access t