More powerAction work.

src/engine/wpak/data/PowerAction.java

@@ -16,7 +16,7 @@ public class PowerAction {
     public int minTrains;
     public int maxTrains;
     public int duration;
-    public String StackingCategory;
+    public String stackingCategory;
     public mbEnums.CompoundCurveType curve;
     public int stackingPriority;
     public mbEnums.CategoryToPowerType categoryToPower;