Created by: portnov
Inspired by this video: https://www.youtube.com/watch?v=PP14rVhgX9M
Unfortunately, Blender does not have API for metaballs similar for bmesh for meshes; Metaballs can only exist in scene. So we cannot "process" metaballs, but we can create them.
This PR introduces a new node, "Metaball out". It has almost all parameters that can be set for metaballs through python API. I put it directly to the Viz category, because I do not think it gonna change a lot.
Documentation is pending.