Leadfoot customizable PCB enclosure

3D printed enclosures tend to be really light. You'd better not sneeze or your latest gizmo blows off your desk. The *Leadfoot* is hollow and can be filled with ballast, such as sand, for added weight. I think this adds an impression of robustness and quality.

The case customizable. See the attached drawing. Of course, the dimensions of the PCB (width, depth, thickness and corner radius) can be altered. Other interesting options are supporting ledgers and spacers. Possible mounting holes can be fastened using "pegs" or screws (drilled spacers) with or without holes for hex nuts.

The two uploaded STL files are:
* A 80x50mm leadfoot with no customization. It uses support ledgers, drilled spacers and M2.5 hex nuts.
* A 1x1.5" enclosure with pegs for the mounting holes. Fits an Adafruit Huzzah breakout perfectly, as shown in the picture.

Some hints for mounting:
* Fill the ballast with a small funnel (I used [this one](https://www.thingiverse.com/thing:2481274)). Plug the hol