More changes!

- Adds ability for modifiers to use a custom _vr sprite file.
- Changes the appearance of the sprite used for the shield overlay.
- Adds ability to color the shield sprite via a multitool.
- More fiddling with numbers...
- Allows rechargers to recharge them to allow for non-recharging variants to recharge.
- Gives shields a default 'cyan' color.
- Adds a mining disk to the equipment vendor to upgrade it.

code/modules/mining/ore_redemption_machine/equipment_vendor.dm

@@ -170,6 +170,7 @@
 		EQUIPMENT("Thalers - 1000",				/obj/item/weapon/spacecash/c1000,									10000),
 		EQUIPMENT("Umbrella",					/obj/item/weapon/melee/umbrella/random,								200),
 		EQUIPMENT("Whiskey",					/obj/item/weapon/reagent_containers/food/drinks/bottle/whiskey,		125),
+		EQUIPMENT("Mining PSG Upgrade Disk",	/obj/item/borg/upgrade/shield_upgrade,								2500),
 	)
 	prize_list["Extra"] = list() // Used in child vendors
 	//VOREStation Edit End