Stackable Post-it Note holder v2

Based on my Stackable Post-it Note holder (http://www.thingiverse.com/thing:495752)
Version 2 (hex.scad, tray.scad, post-it v2.scad, post-it v2.stl)
Modularized, added anti-wrap walls and added hex hole on the bottom
Designed using OpenSCAD 2014.11.05