remove DeathWeapon; IExplodeModifier implemented for resource actors (and for V2, which was the original purpose)

OpenRA.Game/Traits/TraitsInterfaces.cs

@@ -61,6 +61,7 @@ namespace OpenRA.Traits
 	public interface ITerrainCost { float GetTerrainCost(int2 cell, Actor forActor); }
 
 	public interface IDisable { bool Disabled { get; } }
+	public interface IExplodeModifier { bool ShouldExplode(Actor self); }
 
 	public interface IOccupySpace
 	{