Updated license headers

From Qt 5.7 -> tools & tests are licensed under GPL v3 with some
exceptions, see
http://blog.qt.io/blog/2016/01/13/new-agreement-with-the-kde-free-qt-foundation/


Updated license headers to use new GPL-EXCEPT header
(in those files which will be under GPL 3 with exceptions)

Change-Id: I59fcbb8cd1ca42b1a5ef96577bcb35ea0af01b71
Reviewed-by: Kai Koehne <kai.koehne@theqtcompany.com>
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@theqtcompany.com>