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.Common/Activities/Move/AttackMoveActivity.cs

@@ -33,7 +33,7 @@ namespace OpenRA.Mods.Common.Activities
 		{
 			if (autoTarget != null && --scanTicks <= 0)
 			{
-				autoTarget.ScanAndAttack(self);
+				autoTarget.ScanAndAttack(self, true);
 				scanTicks = ScanInterval;
 			}