generally, don't install anything from the top-level examples dirs
automatically. the global README and the aggregator examples.pro are
installed explicitly.

Change-Id: I5f6b8760f37d917b800fa85979896a471778cac0
Reviewed-by: hjk <qthjk@ovi.com>
Reviewed-by: Joerg Bornemann <joerg.bornemann@digia.com>