Blender Git Loki

Fix T63411: Crash adding meta-ball with a small radius

Change how the radius, changing the size of meta plane, sphere & cube.

Previously the size of these primitives would be kept the same,
with only the radius outside the primitive being scaled.

This led to small scale adding a lot of polygons instead
of scaling the primitive down as users would expect.

Also change behavior not to change the resolution when adding
to an existing meta-ball.