Theming: Do not set the global palette

Setting the global palette is not a very good idea, because
it interferes with native styling.

On Windows 7 the dark theme was unuasable, because the text on
all natives controls was to bright.

All native controls and the global palette should be left alone.
Wherever we want styling/theming we have to use Manhatten style.

Change-Id: Ia1d0bfb190e4bde7be72f751afc0846570c1189d
Reviewed-by: hjk <hjk121@nokiamail.com>
support xcode6.1

correctly redirect output, and cleanup pipes
This diverges a bit from upstream, but unfortunately upstream was
not robust.

Change-Id: Icf161e928033299f6078eee0859ac50835b9ffff
Reviewed-by: Eike Ziller <eike.ziller@theqtcompany.com>
Reviewed-by: Fawzi Mohamed <fawzi.mohamed@digia.com>