First step in the attack mechanism's refactor.

Enabled firing multiple armaments at a target simultaneously.
Each armament defines own cursor for targeting.
The force attack modifier influences armament choice for target.
Autotargeting modified to handle firing multiple armaments simultaneously.
As a consequence, healers (medics) no longer require separate Heal
activity and AttackMedic and AutoHeal traits.

OpenRA.Mods.D2k/Traits/AttackSwallow.cs

@@ -8,6 +8,8 @@
  */
 #endregion
 
+using System.Collections.Generic;
+using System.Linq;
 using OpenRA.Mods.Common.Traits;
 using OpenRA.Mods.D2k.Activities;
 using OpenRA.Traits;
@@ -24,6 +26,7 @@ namespace OpenRA.Mods.D2k.Traits
 		public readonly int AttackTime = 30;
 
 		public readonly string WormAttackSound = "Worm.wav";
+
 		public readonly string WormAttackNotification = "WormAttack";
 
 		public override object Create(ActorInitializer init) { return new AttackSwallow(init.Self, this); }
@@ -39,7 +42,7 @@ namespace OpenRA.Mods.D2k.Traits
 			Info = info;
 		}
 
-		public override void DoAttack(Actor self, Target target)
+		public override void DoAttack(Actor self, Target target, IEnumerable<Armament> armaments = null)
 		{
 			// This is so that the worm does not launch an attack against a target that has reached solid rock
 			if (target.Type != TargetType.Actor || !CanAttack(self, target))
@@ -48,7 +51,7 @@ namespace OpenRA.Mods.D2k.Traits
 				return;
 			}
 
-			var a = ChooseArmamentForTarget(target);
+			var a = ChooseArmamentsForTarget(target, true).FirstOrDefault();
 			if (a == null)
 				return;