0.0.12 with large-size smoothing made optional

You can use an m parameter for the command-line mode that's positive, as it always has allowed, to use smoothing, or take the same m parameter and make it negative to disable smoothing for the same sizes. That is, when m is 4 and when m is -4, in both cases 4 sizes will be drawn, but for m = -4 the larger voxels will be pure cubes with no smoothing. This release also fixes some positioning issues with the large-scale models (around the halfway line through the model, the last version would enlarge strangely across the line). This version is encouraged over 0.0.11 because of that positioning fix.