Rework harvester resource claiming:

* Maintains lists of claims, and only restricts
   reservations for friendly units.
 * Removes OnNotifyResourceClaimLost; it's not
   clear whether that is still useful, and it
   prevents future necessary cleanups.
 * Moves other code without changing behaviour.

This fixed stale claims from dead units and enemy
claims from preventing otherwise valid harvest
activities.

OpenRA.Mods.Common/TraitsInterfaces.cs

@@ -28,11 +28,6 @@ namespace OpenRA.Mods.Common.Traits
 		int QuantizedBodyFacings(ActorInfo ai, SequenceProvider sequenceProvider, string race);
 	}
 
-	public interface INotifyResourceClaimLost
-	{
-		void OnNotifyResourceClaimLost(Actor self, ResourceClaim claim, Actor claimer);
-	}
-
 	public interface IPlaceBuildingDecorationInfo : ITraitInfo
 	{
 		IEnumerable<IRenderable> Render(WorldRenderer wr, World w, ActorInfo ai, WPos centerPosition);