Return map & MaplePacketEncoder & Quest status patch

Fixed null pointer issue when trying to use return scroll on maps such as Mu Lung.
Fixed a critical deadlock issue with MaplePacketEncoder.
Fixed a critical DB leak regarding player's quest status.

scripts/npc/2060100.js

@@ -22,11 +22,15 @@
 //carta
 function start(){
     if(cm.isQuestStarted(6301)) {
-        if (cm.haveItem(4000175))
+        if (cm.haveItem(4000175)) {
+            cm.gainItem(4000175, -1);
             cm.warp(923000000, 0);
-        else
+        } else {
             cm.sendOk("In order to open the crack of dimension you will have to posess one piece of Miniature Pianus. Those could be gained by defeating a Pianus.");
-    } else
+        }
+    } else {
         cm.sendOk("I'm #bCarta the sea-witch.#k Don't fool around with me, as I'm known for my habit of turning people into worms.");
+    }
+    
     cm.dispose();
 }