Customizable Laser Diode Rod Clamp

This is a customizable clamp for mounting a laser diode (or other cylindrical objects) on an optics mounting post. The default STLs are for a 12mm diode on an 8mm post with M3 bolts and nuts.

This component was inspired by the [Open-source optics project](http://www.appropedia.org/Open_source_optics), whose goal is to radically reduce the cost of scientific optical hardware, by the [Michigan Tech's Open Sustainability Technology Research Group](http://www.mse.mtu.edu/MOST).

UPDATE: now slightly smaller, using measured sizes (and some leeway) for the nut to reduce slot size. And tighter on the post/rod.