Updated copyright notice

main.py

@@ -1,3 +1,19 @@
+# 
+# Copyright (C) 2021 Thomas Van Acker
+# 
+# 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 <https://www.gnu.org/licenses/>.""")
+# 
+
 import serial
 import time
 import threading