Cellular automaton BlocksCAD snowflake generator

This is a randomizable and customizable cellular automaton snowflake generator in BlocksCAD. It comes in two versions, a 20-level version (board radius up to 20) and a 40-level version. The 40-level version is just barely within the limits of BlocksCAD abilities: BlocksCAD becomes sluggish but it still works (I recommend using Firefox instead of Chrome for much better responsiveness).

A more realistic simulation is [here](https://www.thingiverse.com/thing:2739465).

The automaton puts down