Correct copyright attribution

These files were created and edited in their entirety in commit 8db4bde15d
As far as I can tell they were almost entirety rewritten from their original state.
The old copyright attribution is restored and the new author is added too.

src/gui/torrentoptionsdialog.cpp

@@ -1,6 +1,8 @@
 /*
  * Bittorrent Client using Qt and libtorrent.
- * Copyright (C) 2006  Christophe Dumez <chris@qbittorrent.org>
+ * Copyright (C) 2020  thalieht
+ * Copyright (C) 2011  Christian Kandeler
+ * Copyright (C) 2011  Christophe Dumez <chris@qbittorrent.org>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License

src/gui/torrentoptionsdialog.h

@@ -1,6 +1,8 @@
 /*
  * Bittorrent Client using Qt and libtorrent.
- * Copyright (C) 2006  Christophe Dumez <chris@qbittorrent.org>
+ * Copyright (C) 2020  thalieht
+ * Copyright (C) 2011  Christian Kandeler
+ * Copyright (C) 2011  Christophe Dumez <chris@qbittorrent.org>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License