Fixes server crashing when attempting to drop an empty hand's contained entity. (#66)

* fixes server crash on empty hand drop

Fixes issue with server crashing when client requests for an empty hand to drop its entity.

* fixes drop crash by checking for null in container contains

* removes old change - time to learn to reset properly

Content.Server/GameObjects/ContainerSlot.cs

@@ -31,7 +31,7 @@ namespace Content.Server.GameObjects
         /// <inheritdoc />
         public override bool Contains(IEntity contained)
         {
-            if (contained == ContainedEntity)
+            if (contained != null && contained == ContainedEntity)
                 return true;
             return false;
         }