Remove unused usings

OpenRA.Mods.RA/AI/RushFuzzy.cs

@@ -12,8 +12,6 @@ namespace OpenRA.Mods.RA.AI
 {
 	class RushFuzzy : AttackOrFleeFuzzy
 	{
-		public RushFuzzy() { }
-
 		protected override void AddingRulesForNormalOwnHealth()
 		{
 			AddFuzzyRule("if ((OwnHealth is Normal) " +

OpenRA.Mods.RA/AI/Squad.cs

@@ -8,10 +8,8 @@
  */
 #endregion
 
-using System;
 using System.Collections.Generic;
 using System.Linq;
-using OpenRA.FileFormats;
 using OpenRA.Traits;
 using XRandom = OpenRA.Thirdparty.Random;
 

OpenRA.Mods.RA/AI/States/GroundStates.cs

@@ -8,7 +8,6 @@
  */
 #endregion
 
-using System.Collections.Generic;
 using System.Linq;
 using OpenRA.Traits;
 

OpenRA.Mods.RA/AI/States/ProtectionStates.cs

@@ -8,10 +8,6 @@
  */
 #endregion
 
-using System.Collections.Generic;
-using System.Linq;
-using OpenRA.Traits;
-
 namespace OpenRA.Mods.RA.AI
 {
 	class UnitsForProtectionIdleState : GroundStateBase, IState