renamed VictoryConditions -> ConquestVictoryConditions in prep for adding a custom map

OpenRA.Game/Traits/TraitsInterfaces.cs

@@ -134,4 +134,6 @@ namespace OpenRA.Traits
 
 	public interface IRenderOverlay { void Render(); }
 	public interface INotifyIdle { void Idle(Actor self); }
+
+	public interface IVictoryConditions { bool HasLost { get; } bool HasWon { get; } }
 }