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.

build/built-jar.properties

@@ -1,4 +1,4 @@
-#Fri, 18 Aug 2017 19:17:13 -0300
+#Wed, 23 Aug 2017 17:38:01 -0300
 
 
 C\:\\Nexon\\MapleSolaxia\\MapleSolaxiaV2=