Parametric stackable workshop bins/boxen V2

Redesigned my little plastic bins from scratch now that I actually kind-of-sort-of know what I'm doing. Perfect for storing various little widgets and doodads. I've included three default variants and the `.scad` file has many more options for you to edit (see below). Bins that are the same width are all compatible with each other (stacking largest to smallest).

#### Recommended Print Settings
- 0.4mm nozzle
- 0.2mm layer height
- 10% infill
- No supports
- Any filament that isn't flexible
- Print as oriented

#### Parameters
- `width` (number): Width of the bin (does not include the lip)
- `depth` (number): Depth of the bin (does not include the lip or spout)
- `height` (number): Height of the bin (does not include the lip)
- `spoutHeight` (number): Height of the spout at the front (I recommend less than `( height / 2 )`)
- `spoutDepth` (number): Depth of the spou