Box with honeycomb hole pattern

A practice using OpenSCAD to create honeycomb holes for cubic boxes, inspired by [Box with Hexagonal Holes (by pmoews)](http://www.thingiverse.com/thing:21593) and [Customizable drawer box with hex pattern sides (by gpvillamil)](http://www.thingiverse.com/thing:421886).

The box has an interior of 50mm and thickness 1.5mm, which can hold my [Printable Interlocking Puzzle Remix](http://www.thingiverse.com/thing:569118) (Originally by [richgain](http://www.thingiverse.com/thing:31639) or [Cube P