Remove passing the warheads from DamageWarhead to AttackInfo.

Added a Damage class to pass damage value and damage(types) instead.
This removes a great amount of overhead and longterm opens possibilities to have damagetypes without warheads.

OpenRA.Mods.Common/Traits/Sound/DeathSounds.cs

@@ -39,11 +39,8 @@ namespace OpenRA.Mods.Common.Traits.Sound
 
 		public void Killed(Actor self, AttackInfo e)
 		{
-			var warhead = e.Warhead as DamageWarhead;
-
-			// If the warhead is null, the actor was killed by some non-standard means
-			if (info.DeathTypes.Count == 0 || (warhead != null && warhead.DamageTypes.Overlaps(info.DeathTypes)))
+			if (info.DeathTypes.Count == 0 || e.Damage.DamageTypes.Overlaps(info.DeathTypes))
 				self.PlayVoiceLocal(info.Voice, info.VolumeMultiplier);
 		}
 	}
-}
+}