Simple Parametric Fastener Pin Generator Module

SummaryI needed a module to generate simple flared pins for fastening things together in prints, removing the need for hardware nuts and bolts. I wanted it to be as short, simple, and easy to use as possible, and to fit in a single module that can be integrated into other openscad scripts and designs. I am sharing this as public domain. You may use it in any of your own things or customizers. Attribution is appreciated but not required. examples in the code.