paramchain: re-parametric OpenSCAD library from Open Cable Chain

Why one more cable chain?
I decided to add some cable chains to better control the cables position in my 3Drag. I start looking in Thingiverse for a "good" cable chain. My needs:
1) "open" because my 3Drag is now fully built.
2) "large" or parametric, because 3Drag uses flat cables.
I found some interesting designs, e.g. i tested http://www.thingiverse.com/thing:868040. But my printer was making large "spider webbing", calling for a long cleanning time for every element.... One more need:
3) "little work after printing".

The winner was 'Open Cable Chain' (http://www.thingiverse.com/thing:611593), requiring very little work after printing.

But 'Open Cable Chain' is not large enough for my 3Drag flat cables, so I re-make this parametric library, starting from some .stl files by Claghorn.

The "paramchain" library builds open cable chain elements and chain ends having parametric size, in three options:
A type, rotating 0:45°, standard