Features:

Moved handling for transport belts, splitters, and underground belts into this mod
Added startup settings "Reskin entities", "Reskin equipment", "Reskin items and fluids" and "Reskin technologies" to control the scope of the various mod reskin toggles; by default the complete scope is enabled
Added function check_scope to check the enabled scope and the given toggle setting and return the appropriate boolean or nil
Added control logic to check for missing Artisanal Reskins mods and notify players once per save
Added a setting "Display notifications" under Player settings to control whether update notifications display

Changes:

Revised tint handling, separated transport belt tints into their own table, reskins.lib.belt_tint_index
Revised how tints are indexed, allowing for direct reference by tier-number instead of a string
Revised transport belt mask sprites to improve mask precision and color
Consolidated settings-stage functions into reskins.lib global function host
Internal code revisions such that reskinning is trigger-based
Revised update notification handling; messages sent by this mod will be sent to admins only (since only they can make mod changes)
Images are now losslessly compressed, instead of lossy; there is a modest increase in filesize

Fixed that the concatenation routine to append the defaults for boolean settings did not handle LocalisedStrings properly