Experimental DB pool + fixed stat overflow on equips

Implemented EXPERIMENTAL DBCP (connection pool), trying to improve
concorrent access to DB. Added door portals on Kerning Square. Fixed
equipments getting stat overflow when upgrading stats. Fixed expiring
pets crashing the client in some cases.

src/scripting/event/EventInstanceManager.java

@@ -57,6 +57,7 @@ import client.Skill;
 import constants.ItemConstants;
 import constants.ServerConstants;
 import java.awt.Point;
+import java.sql.Connection;
 import java.util.concurrent.ScheduledFuture;
 import java.util.logging.Level;
 import java.util.logging.Logger;
@@ -570,13 +571,16 @@ public class EventInstanceManager {
 
 	public void saveWinner(MapleCharacter chr) {
 		try {
-			try (PreparedStatement ps = DatabaseConnection.getConnection().prepareStatement("INSERT INTO eventstats (event, instance, characterid, channel) VALUES (?, ?, ?, ?)")) {
+                        Connection con = DatabaseConnection.getConnection();
+			try (PreparedStatement ps = con.prepareStatement("INSERT INTO eventstats (event, instance, characterid, channel) VALUES (?, ?, ?, ?)")) {
 				ps.setString(1, em.getName());
 				ps.setString(2, getName());
 				ps.setInt(3, chr.getId());
 				ps.setInt(4, chr.getClient().getChannel());
 				ps.executeUpdate();
 			}
+                        
+                        con.close();
 		} catch (SQLException ex) {
 			ex.printStackTrace();
 		}