Add copyright to extra_features_utils.py

Author: Jaquier Aurélien Tristan

bluepyopt/ephys/extra_features_utils.py

@@ -1,3 +1,24 @@
+"""Extra features functions"""
+
+"""
+Copyright (c) 2016-2020, EPFL/Blue Brain Project
+
+ This file is part of BluePyOpt <https://github.com/BlueBrain/BluePyOpt>
+
+ This library is free software; you can redistribute it and/or modify it under
+ the terms of the GNU Lesser General Public License version 3.0 as published
+ by the Free Software Foundation.
+
+ This library 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 Lesser General Public License for more
+ details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with this library; if not, write to the Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+"""
+
 import numpy as np
 
 all_1D_features = [