chore: add license headers

Author: javier-godoy

src/test/java/com/flowingcode/addons/applayout/ApplayoutDemoView.java

@@ -1,3 +1,22 @@
+/*-
+ * #%L
+ * App Layout Addon
+ * %%
+ * Copyright (C) 2018 - 2020 Flowing Code
+ * %%
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * #L%
+ */
 package com.flowingcode.addons.applayout;
 
 import java.io.BufferedReader;

src/test/java/com/flowingcode/addons/applayout/InternalView.java

@@ -1,3 +1,22 @@
+/*-
+ * #%L
+ * App Layout Addon
+ * %%
+ * Copyright (C) 2018 - 2020 Flowing Code
+ * %%
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * #L%
+ */
 package com.flowingcode.addons.applayout;
 
 import com.vaadin.flow.component.html.Div;

src/test/java/com/flowingcode/addons/applayout/test/SerializationTest.java

@@ -1,3 +1,22 @@
+/*-
+ * #%L
+ * App Layout Addon
+ * %%
+ * Copyright (C) 2018 - 2020 Flowing Code
+ * %%
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * #L%
+ */
 package com.flowingcode.addons.applayout.test;
 
 import java.io.ByteArrayInputStream;
@@ -30,4 +49,4 @@ public void testSerialization() throws ClassNotFoundException, IOException {
 		testSerializationOf(appLayout);
 	}
 
-}
+}