added comments to python files 1/2

Former-commit-id: 52d0f35689

python/py_igl/py_streamlines.cpp

@@ -1,3 +1,10 @@
+// This file is part of libigl, a simple c++ geometry processing library.
+//
+// Copyright (C) 2017 Sebastian Koch <s.koch@tu-berlin.de> and Daniele Panozzo <daniele.panozzo@gmail.com>
+//
+// This Source Code Form is subject to the terms of the Mozilla Public License
+// v. 2.0. If a copy of the MPL was not distributed with this file, You can
+// obtain one at http://mozilla.org/MPL/2.0/.
 py::class_<igl::StreamlineData> StreamlineData(m, "StreamlineData");
 StreamlineData
 .def(py::init<>())