Make oil derricks repairable by engineers

OpenRA.Mods.RA/EngineerRepair.cs

@@ -61,7 +61,7 @@ namespace OpenRA.Mods.RA
 			public override bool CanTargetActor(Actor self, Actor target, bool forceAttack, bool forceQueued, ref string cursor)
 			{
 				if( !base.CanTargetActor( self, target, forceAttack, forceQueued, ref cursor ) ) return false;
-				if (!target.HasTrait<RepairableBuilding>())
+				if (!target.HasTrait<EngineerRepairable>())
 					return false;
 
 				if (self.Owner.Stances[ target.Owner ] != Stance.Ally)
@@ -75,4 +75,8 @@ namespace OpenRA.Mods.RA
 			}
 		}
 	}
+
+	class EngineerRepairableInfo : TraitInfo<EngineerRepairable> { }
+
+	class EngineerRepairable { }
 }

mods/ra/rules/civilian.yaml

@@ -289,6 +289,7 @@ OILB:
 		Range: 3
 	Capturable:
 	CapturableBar:
+	EngineerRepairable:
 	-MustBeDestroyed:
 	CashTrickler:
 		Period: 250

mods/ra/rules/defaults.yaml

@@ -200,6 +200,7 @@
 	RenderBuilding:
 	WithBuildingExplosion:
 	RepairableBuilding:
+	EngineerRepairable:
 	EmitInfantryOnSell:
 		ActorTypes: e1,e1,e1,e1,e1,e1,e1,e1,e1,e1,e1,e1,e1,e1,e1,c1,c2,c3,c4,c5,c6,c7,c8,c9,c10,e6,e6,e6,e6,e6
 	MustBeDestroyed:
@@ -253,6 +254,7 @@
 ^TechBuilding:
 	Inherits: ^Building
 	-RepairableBuilding:
+	-EngineerRepairable:
 	Health:
 		HP: 400
 	Armor: