More enum work.

src/engine/wpak/PowerEntry.java

@@ -18,7 +18,7 @@ public class PowerEntry {
     public ArrayList<PowerData> powers = new ArrayList<>();
     public mbEnums.PowerTargetType target_type;
     public int range;
-    public String areaType;
+    public mbEnums.AreaType areaType;
     public int areaRange;
     public String excludeType;
     public mbEnums.CostType costType;