Fix checkstyle

Signed-off-by: Daniele Ricci <[email protected]>

app/src/test/java/org/kontalk/client/NumberValidatorTest.java

@@ -1,3 +1,21 @@
+/*
+ * Kontalk Android client
+ * Copyright (C) 2016 Kontalk Devteam <[email protected]>
+
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
 package org.kontalk.client;
 
 import org.junit.Test;