QtWebKit build system cleanup
The idea is to clean up and improve how we use Qmake to build QtWebKit.
Remove Symbian support
Laszlo will put up a patch.
Remove QTDIR_build and package-build
Can do straight away, before 4.8 is released, since we already branched 2.2
Add top level (root) pro-file for organizing the project (for QtCreator)
Use subdirs for derived sources instead of relying on build-webkit
Use CONFIG+=GNUMake when present to improve dependency tracking
- Move SBOX_CHECK to helpers.pri
- Move qt5-helper to helpers.pri