APC & SMES appearances. (#78)

* CEV-Eris SMES sprite as RSI.

Has been modified so that the light overlay states use alpha blending.

* Add tiny glow to SMES display sprite.

* Appearances work v2

* More WiP

* RoundToLevels works correctly on even level counts now.

* SMES -> Smes because MS guidelines.

* CEV-Eris APC sprite.

* APC visuals.

* Reduce SMES scale again to normal levels.

* Update submodule

Content.Server/GameObjects/Components/Power/ApcComponent.cs

@@ -0,0 +1,50 @@
+using Content.Shared.GameObjects.Components.Power;
+using SS14.Server.GameObjects;
+using SS14.Shared.GameObjects;
+
+namespace Content.Server.GameObjects.Components.Power
+{
+    public class ApcComponent : Component
+    {
+        public override string Name => "Apc";
+
+        PowerStorageComponent Storage;
+        AppearanceComponent Appearance;
+
+        ApcChargeState LastChargeState;
+
+        public override void Initialize()
+        {
+            base.Initialize();
+            Storage = Owner.GetComponent<PowerStorageComponent>();
+            Appearance = Owner.GetComponent<AppearanceComponent>();
+        }
+
+        public override void Update(float frameTime)
+        {
+            var newState = CalcChargeState();
+            if (newState != LastChargeState)
+            {
+                LastChargeState = newState;
+                Appearance.SetData(ApcVisuals.ChargeState, newState);
+            }
+        }
+
+        ApcChargeState CalcChargeState()
+        {
+            var storageCharge = Storage.GetChargeState();
+            if (storageCharge == ChargeState.Discharging)
+            {
+                return ApcChargeState.Lack;
+            }
+
+            if (storageCharge == ChargeState.Charging)
+            {
+                return ApcChargeState.Charging;
+            }
+
+            // Still.
+            return Storage.Full ? ApcChargeState.Full : ApcChargeState.Lack;
+        }
+    }
+}