Blender Git Loki

Revert "Multi-Objects: ARMATURE_OT_armature_layers

This reverts commits:
* 29a281f9ef5b3a577e6d658892a704b509d718ef
* 3a8b56ce24c9228a885d3c44f4c22d90be04ae4c

This operator shouldn't behave multi-objects. This would only work
if all the selected objects had the same logic for their layers,
which may be likely for characters, but it won't be for mixing props and
characters.