Hardcoded includes in global.h.in

I can read in that file:

#include <QtUiTools/QtUiTools>
#include <QtMultimedia/QtMultimedia>
#include <QtSvg/QtSvg>
#include <QtHelp/QtHelp>

These include are systematically there even if the corresponding packages are not installed (e.g. my system only as qtbase and qtdeclarative).

There should be a logic to not include them if the packages are not detected.