create StrictObject base class
move disk_group_name validation to Disk::Group
extract _reallocate into Reallocator object
StrictObject dies if SUPER::create fails
remove unused import
extract _move to Mover object
formatting
formatting
move move_shadow_params to Mover
push shadow allocation params into method
rename move_shadow_params to _get_move_shadow_params
rename move_shadow_path to _get_move_shadow_path
fix idempotent move test

This test reaches into the internals of the Mover.
formatting
extract _{un,}archive to {Una,A}rchiver
formatting