Fix license header

Signed-off-by: Lixfel <agga-games@gmx.de>

src/de/steamwar/bungeecore/comms/handlers/PrepareSchemHandler.java

@@ -1,3 +1,22 @@
+/*
+    This file is a part of the SteamWar software.
+
+    Copyright (C) 2020  SteamWar.de-Serverteam
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Affero 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 Affero General Public License for more details.
+
+    You should have received a copy of the GNU Affero General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+*/
+
 package de.steamwar.bungeecore.comms.handlers;
 
 import com.google.common.io.ByteArrayDataInput;