ThreadTracker + Attempt on NPC Disappearing fix

Engineered the ThreadTracker: server-embedded deadlock auditing tool, which will print error messages in case of found deadlocks (also showing all in-use locks on the time of the issue).
Changed the player's id on DB now starting from 20mil, thus preventing players from overwriting NPC/mobs with same oid in-game. Requires proper testing to see if the issue has been cleared.

src/server/maps/MapleMiniDungeon.java

@@ -25,8 +25,9 @@ import java.util.List;
 import java.util.ArrayList;
 import java.util.concurrent.ScheduledFuture;
 import java.util.concurrent.locks.Lock;
-import java.util.concurrent.locks.ReentrantLock;
+import tools.locks.MonitoredReentrantLock;
 import tools.MaplePacketCreator;
+import tools.locks.MonitoredEnums;
 
 /**
  *
@@ -35,7 +36,7 @@ import tools.MaplePacketCreator;
 public class MapleMiniDungeon {
     List<MapleCharacter> players = new ArrayList<>();
     ScheduledFuture<?> timeoutTask = null;
-    Lock lock = new ReentrantLock(true);
+    Lock lock = new MonitoredReentrantLock(MonitoredEnums.MINIDUNGEON, true);
     
     int baseMap;
     long expireTime;