Blender Git Loki

Cleanup of previous rBac723db57fd8ba5 commit.

Simplify a bit, and remove some now redundant remappings.

As a side note, rBac723db57fd8ba5 actually also fixed some unreported
issues (missing remappings to new objects/collections in new copied
scene, that were not previously handled by the 'custom' code).

There are almost certainly still some missing remappings around,
though...