Optimized equip levelup method + Ultra three snails feature

Fixed performance drop on the server when trying to level up equipments
which has high stats points. Added a flag enabling massive damages with
Three Snails skill.

src/server/life/MapleMonster.java

@@ -371,8 +371,8 @@ public class MapleMonster extends AbstractLoadedMapleLife {
             }
             
             attacker.gainExp(personalExp, partyExp, true, false, isKiller);
-            attacker.mobKilled(getId());
             attacker.increaseEquipExp(personalExp);
+            attacker.mobKilled(getId());
         }
     }