Compact Folding Dice Tower

Modified tray for http://www.thingiverse.com/thing:700507

In printing out MementoMori's version of saiyanslayer's excellent compact dice tower, I had a difficult time getting the tray to detach from the bed without tearing the tray portion off. This was due to there just not being that much surface area for the tray to adhere to the tray frame, making it very weak.

I added a reinforcement bar to the inside bottom of the tray, and increased the frame size by 1mm in each direction. That made