Flying entity exemption.

src/main/java/com/songoda/ultimatestacker/tasks/StackingTask.java

@@ -67,6 +67,7 @@ public class StackingTask extends BukkitRunnable {
                         && initalEntity.getMetadata("US_REASON").get(0).asString().equals("SPAWNER"))
 
                         || Setting.ONLY_STACK_ON_SURFACE.getBoolean()
+                        && !canFly(initalEntity)
                         && (!initalEntity.isOnGround() && !initalEntity.getLocation().getBlock().isLiquid()))
                     continue;
 
@@ -134,4 +135,15 @@ public class StackingTask extends BukkitRunnable {
             removed.clear();
         }
     }
+
+    private boolean canFly(LivingEntity entity) {
+        switch (entity.getType()) {
+            case GHAST:
+            case BLAZE:
+            case PHANTOM:
+                return true;
+            default:
+                return false;
+        }
+    }
 }

src/main/java/com/songoda/ultimatestacker/utils/settings/Setting.java

@@ -93,7 +93,7 @@ public enum Setting {
 
     ONLY_STACK_ON_SURFACE("Entities.Only Stack On Surface", false,
             "Should entities only be stacked if they are touching the ground",
-            "or swimming?"),
+            "or swimming? This does not effect flying entities."),
 
     STACK_ITEMS("Items.Enabled",true,
                         "Should items be stacked?"),