Added LICENSE

src/test/java/net/ivoa/xml/vospace/v2/TransferTest.java

+/*
+ * This file is part of vospace-datamodel
+ * Copyright (C) 2021 Istituto Nazionale di Astrofisica
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
 package net.ivoa.xml.vospace.v2;
 
 import com.fasterxml.jackson.databind.ObjectMapper;