Modified Parametric Box with Lid

Needed a box for something and saw LBussy's box.

http://www.thingiverse.com/thing:1918169

I had played a bit with OpenSCAD so tinkered to add a few things I wanted:

-optional vent shapes
-option to add embossed text on the lid. (note easy to make the text go all the way through, but since some characters like a 'O' would leave a hollow center I made it just emboss..)
-option to display just main box or lid so can create stl's of individual parts

v4
For Vent Type (hType) 4 added holes in both directions
slightly better centering of holes
v4
Modified to put holes in top and bottom of the box. It is a bit of a dirty fix but works for not too large boxes..really need to rewrite this myself properly such that can space things correctly.