Customizable Ultimate Drawer System Drawer

# Ultimate Drawer System
Intended to be the ultimate drawer system that is
* printable with FDM printing
* optimizable for anything you store in drawers
* compatible with Thingiverse's Customizer
* written for ease of improvement (which could use some improvement)

This Thing is the drawer customizer. For the shelving unit customizer, see [Customizable Ultimate Drawer System Shelf](https://www.thingiverse.com/thing:3796410). For drawer inserts (dividers) see [Customizable Ultimate Drawer System Inserts](https://www.thingiverse.com/thing:3798783).

## The System
* Drawers and complementary shelving units are sized in units called "Us".
* If only one dimension is given, it is assumed to be the height and the width and depth are assumed to be 1U.
* A 1U drawer is 120 mm wide by 120 mm deep by 19 mm high.
* A 2U drawer is 120 mm wide by 120 mm deep by 39 mm high.
* Actual drawer width is 131 * Us wide - 10 mm
* Actual drawer depth is 130 * Us deep - 10 mm
* Actual drawer he