Durable Steps for Spiral Dice Tower

I found the original steps often stuck, requiring additional force to turn and sometimes breaking the stubs for controlling the opening angle.

I increased the stub size and cutout to make assembly and use easier. Simplifying further, the standard step can be used as the bottom step with reasonable tolerances.

**You will need the longer box and [single column](https://www.thingiverse.com/thing:4782579)** which further improve durability.

Part count:
* 19 - standard step
* 1 - top step

Overall, I found the part easier to print, assemble, and use. I hope you enjoy!