E3D V6 in OpenSCAD

An E3D V6 in OpenSCAD for checking fitment of mounts or fan ducts or stuff like that.

This is accurate to the E3D drawings as of December 2017. There's an STL with no heatsink duct, and there's an STL which uses the [actual E3D heatsink duct model by Josh from E3D](https://www.thingiverse.com/thing:340312).

I couldn't find one which was accurate to the E3D drawings so I made my own. I was most concerned with the nozzle height, not making the heater block and fan extremely accurate. The silicone sock is modelled for horizontal fit only.