Hornday LnL Peg Board Die Holder

I customized https://www.thingiverse.com/thing:537516 to hold three reloading dies inserted into Hornady Lock-n-Load Die Bushings. Here are the OpenSCAD parameters I used:

```
// width of the orifice
holder_x_size = 28;

// depth of the orifice
holder_y_size = 28;

// hight of the holder
holder_height = 15;

// how thick are the walls. Hint: 6*extrusion width produces the best results.
wall_thickness = 7;

// how many times to repeat the holder on X axis
holder_x_count = 3;

/