Adds sized (S, M, L) power cells and a generic component for battery powered items (#2352)

* Refactor battery/powercell assets and add new ones.

* committing before I fuck things up

* slot component doned I think

* dictionary update

* Fixes

* Moving flashlight to powerslotcomponent

* har har i am using the message tubes

* Better documentation comment

* Reverting this overengineered garbage.

* Off with ye I said

* Examine texts.

* Some minor fixes to IDE complaints

* slot size from yaml

* Ignored component + removing a useless typo entry

* Making stunbatons use this

* Handle the message and remove some unnecessary dirtiness

* actionblocker checks

* remove unused file

* remove updatevisual

* make these nullable

* make these nullable too

* Unrename sprite folder

* check itemcomponent on insertion

* Use SendMessage over Owner.SendMessage

* Add support for auto-recharging batteries, an auto-recharging cell, and make flashlight status update correctly if one is inserted in it.

* get rid of public fields which are Bad

* add a description for the stun baton while i'm in here

* one more public field

* Add the blinky animation to the atomic cell

* Fix the charge indicator being STUPID

* better comments

* this is a better function

* add pause for flashlight, remove unnecessary imports from battery

* potato battery copyright link

* WHO DID THAT

* mr clean has come

* Random pitch

* pausing

* round to nearest levels

Content.Client/GameObjects/Components/Power/PowerCellVisualizer.cs

@@ -36,7 +36,8 @@ namespace Content.Client.GameObjects.Components.Power
             var sprite = component.Owner.GetComponent<ISpriteComponent>();
             if (component.TryGetData(PowerCellVisuals.ChargeLevel, out float fraction))
             {
-                sprite.LayerSetState(Layers.Charge, $"{_prefix}_{ContentHelpers.RoundToLevels(fraction, 1, 5) * 25}");
+                int level = ContentHelpers.RoundToNearestLevels(fraction, 1, 4) * 25;
+                sprite.LayerSetState(Layers.Charge, $"{_prefix}_{level}");
             }
         }