Added Storage's "Arrange Items" + Fixed equipped pet on CS issue

Implemented the "Arrange Items" Storage feature (merge & sort items on the Storage). Fixed items from different ownerships being merged together when trying to swap their positions. Fixed a bug where putting equipped pets onto Cash Shop inventory would cause a crash the returning to the game.

src/server/MapleStorage.java

@@ -27,6 +27,7 @@ import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
 import java.util.ArrayList;
+import java.util.Collection;
 import java.util.Collections;
 import java.util.Comparator;
 import java.util.HashMap;
@@ -266,6 +267,23 @@ public class MapleStorage {
             lock.unlock();
         }
     }
+    
+    public void arrangeItems(MapleClient c) {
+        lock.lock();
+        try {
+            MapleStorageInventory msi = new MapleStorageInventory(c, items);
+            msi.mergeItems();
+            items = msi.sortItems();
+            
+            for (MapleInventoryType type : MapleInventoryType.values()) {
+                typeItems.put(type, new ArrayList<>(items));
+            }
+
+            c.announce(MaplePacketCreator.arrangeStorage(slots, items));
+        } finally {
+            lock.unlock();
+        }
+    }
 
     public int getMeso() {
         return meso;