Fixed double closing of connections

Author: x7airworker

src/main/java/org/javawebstack/orm/connection/pool/PooledSQL.java

@@ -48,6 +48,9 @@ public void close(ResultSet resultSet) {
     }
 
     public void close() {
+        if (closed)
+            return;
+
         pool.release(connection);
         closed = true;
     }