Updated Meso & Arrow drops + Aran change jobs fix + improved concurrency

Added meso drop data for many mobs that were missing mesos.
Enhanced arrow drop data, now dropping bundles instead of unitary items.
Fixed issues with several Aran change jobs crashing the player shortly after changing jobs.
Improved concurrency in MapleGuild, MapleAlliance and MaplePlayerShop.
New tools: MapleArrowFetcher and MapleMesoFetcher, that were used to compile the updated drop data info.

tools/MapleArrowFetcher/src/tools/DatabaseConnection.java

@@ -0,0 +1,51 @@
+package tools;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+
+/**
+ * @author Frz (Big Daddy)
+ * @author The Real Spookster (some modifications to this beautiful code)
+ */
+public class DatabaseConnection {
+    private static String DB_URL = "jdbc:mysql://localhost:3306/maplesolaxia";
+    private static String DB_USER = "root";
+    private static String DB_PASS = "";
+    
+    public static final int RETURN_GENERATED_KEYS = 1;
+
+    private static ThreadLocal<Connection> con = new ThreadLocalConnection();
+
+    public static Connection getConnection() {
+        Connection c = con.get();
+        try {
+            c.getMetaData();
+        } catch (SQLException e) { // connection is dead, therefore discard old object 5ever
+            con.remove();
+            c = con.get();
+        }
+        return c;
+    }
+
+    private static class ThreadLocalConnection extends ThreadLocal<Connection> {
+
+        @Override
+        protected Connection initialValue() {
+            try {
+                Class.forName("com.mysql.jdbc.Driver"); // touch the mysql driver
+            } catch (ClassNotFoundException e) {
+                System.out.println("[SEVERE] SQL Driver Not Found. Consider death by clams.");
+                e.printStackTrace();
+                return null;
+            }
+            try {
+                return DriverManager.getConnection(DB_URL, DB_USER, DB_PASS);
+            } catch (SQLException e) {
+                System.out.println("[SEVERE] Unable to make database connection.");
+                e.printStackTrace();
+                return null;
+            }
+        }
+    }
+}