Added copyright.

Added note about incompatibility with new versions of Java.

build.gradle

@@ -1,3 +1,35 @@
+/*
+* build.gradle
+*
+* Copyright (c) 2018, Erik C. Thauvin (erik@thauvin.net)
+* All rights reserved.
+*
+* Redistribution and use in source and binary forms, with or without
+* modification, are permitted provided that the following conditions are met:
+*
+*   Redistributions of source code must retain the above copyright notice, this
+*   list of conditions and the following disclaimer.
+*
+*   Redistributions in binary form must reproduce the above copyright notice,
+*   this list of conditions and the following disclaimer in the documentation
+*   and/or other materials provided with the distribution.
+*
+*   Neither the name of this project nor the names of its contributors may be
+*   used to endorse or promote products derived from this software without
+*   specific prior written permission.
+*
+* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
 class TestPlugin implements Plugin<Project> {
     void apply(Project project) {
         project.task('runPlugin') {