0.0.13 with output organized into folders

This should produce exactly the same renders as the last release, but now it organizes the output into folders based on scale and effects that wouldn't typically be mixed in art or a game. Usage.txt has been updated, and the information when you run IsoVoxel.exe with no arguments has also received attention. This is meant to address #8 , but should be generally more pleasant to work with when you only want some of the many rendered images.