Improved item & drop-point checking + Dojo fixes + Duey revamp

Fixed some issues with items being dropped sometimes out-of-reach and in a weird way.
Improved item checking function, now looking up one-of-a-kind items properly.
Fixed some issues with dojo skills and possible exploits in dojo progression.
Improved Duey, now displaying better info to players.

src/server/MapleTrade.java

@@ -194,7 +194,7 @@ public class MapleTrade {
     private boolean fitsInInventory() {
         List<Pair<Item, MapleInventoryType>> tradeItems = new LinkedList<>();
         for (Item item : exchangeItems) {
-            tradeItems.add(new Pair(item, MapleItemInformationProvider.getInstance().getInventoryType(item.getItemId())));
+            tradeItems.add(new Pair(item, item.getInventoryType()));
         }
         
         return MapleInventory.checkSpotsAndOwnership(chr, tradeItems);