Show all of the internal included files in the Supporting Files group

In XCode only the pro file was shown in the Supporting Files group as
it was the first one in the list. The others were not shown as it was
recreating the temporary QStringList each time instead of appending to
it.

Change-Id: Ifbc40a25156cf639eaa34b410f534726c41b6232
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@digia.com>
CMake: Add defines for disabled features.

Change-Id: I883291dc72eef82aaea2e2b039dfb33c7f56e98b
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>
Reviewed-by: Stephen Kelly <stephen.kelly@kdab.com>