Make weapon can target attacker itself an option.

OpenRA.Game/GameRules/WeaponInfo.cs

@@ -99,6 +99,9 @@ namespace OpenRA.GameRules
 		[Desc("Number of shots in a single ammo magazine.")]
 		public readonly int Burst = 1;
 
+		[Desc("Can this weapon target attacker itself.")]
+		public readonly bool CanTargetSelf = false;
+
 		[Desc("What types of targets are affected.")]
 		public readonly BitSet<TargetableType> ValidTargets = new BitSet<TargetableType>("Ground", "Water");
 
@@ -206,6 +209,9 @@ namespace OpenRA.GameRules
 		/// <summary>Checks if the weapon is valid against (can target) the actor.</summary>
 		public bool IsValidAgainst(Actor victim, Actor firedBy)
 		{
+			if (!CanTargetSelf && victim == firedBy)
+				return false;
+
 			var targetTypes = victim.GetEnabledTargetTypes();
 
 			if (!IsValidTarget(targetTypes))
@@ -222,6 +228,9 @@ namespace OpenRA.GameRules
 		/// <summary>Checks if the weapon is valid against (can target) the frozen actor.</summary>
 		public bool IsValidAgainst(FrozenActor victim, Actor firedBy)
 		{
+			if (!CanTargetSelf && victim.Actor == firedBy)
+				return false;
+
 			if (!IsValidTarget(victim.TargetTypes))
 				return false;