Add missing license notice

src/options.ts

@@ -1,3 +1,19 @@
+/* This file is part of PeerTubeify.
+ *
+ * PeerTubeify 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.
+ *
+ * PeerTubeify 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
+ * PeerTubeify. If not, see <https://www.gnu.org/licenses/>.
+ */
+
 import * as _ from 'lodash/fp';
 
 function id(id: string): Element { return document.getElementById(id); }