Filament Sample Reel

**V2 Update**

I've added a set of V2 parts. The V2 parts should be backward-compatible with all V1 parts, however, there are improvements:

* The Screw end has 1 mm shorter threads to ensure that the parts screw together with no gap on the inside
* The Screw end now has keeper holes for both 1.75 mm and 3 mm filament
* Bases are now available in 60 mm (V1 size), 40 mm, 30 mm, and 20 mm widths

The 40 mm was a bit too wide to save any room in my filament box, and the 20 mm was too narrow