Move Access & AccessReader to shared. (#5798)

* git mv

* Move Access Component & system.

- Name space changes
- Rename AccessReader to AccessReaderComponent
- Also need an abstract TryGetSlot function for SharedInventoryComponent

* better TryGetSlot

* Ah yes, tests exist.

Content.Shared/Inventory/SharedInventoryComponent.cs

@@ -1,6 +1,6 @@
 using System;
 using System.Collections.Generic;
-using Content.Shared.Movement.Components;
+using System.Diagnostics.CodeAnalysis;
 using Robust.Shared.GameObjects;
 using Robust.Shared.GameStates;
 using Robust.Shared.IoC;
@@ -42,6 +42,8 @@ namespace Content.Shared.Inventory
             InventoryInstance = DynamicTypeFactory.CreateInstance<Inventory>(type!);
         }
 
+        public abstract bool TryGetSlot(Slots slot, [NotNullWhen(true)] out EntityUid? item);
+
         /// <returns>true if the item is equipped to an equip slot (NOT inside an equipped container
         /// like inside a backpack)</returns>
         public abstract bool IsEquipped(EntityUid item);