Parametric Flashlight Diffuser

This module produces a diffuser cap for flashlights so they can be used for ambient lighting.

For obvious reasons, this works best with translucent filaments (I've been using MatterHackers' Clear Translucent Pro PLA).

#### Instructions

Print test parts to dial in the proper diameter:

1. Measure the widest point at the top of your flashlight.
2. Set the `diameter` property to this value **plus** .5-1mm to
account for thermal shrinkage.
3. Set the `diffuser_type` to `None`.
4. S