gender/slenthem pin

Replacement pin for Javanese gamelan instruments - can be modified to fit gender barung, gender panerus, or slenthem. Detailed directions are given in the readme file and the OpenSCAD file.

Seems reasonably strong at 50% infill. Needs to be printed with supports. Would look much smoother with a smaller layer height, but as it's not a highly visible part I didn't worry about it.