Qt5 compatibility update

Changes done to compile with Qt5 - [qt5 only] means it is conditionally applied based on Qt version.
* [qt5 only] corrected include files (reflect changes in Qt5 includes)
* [qt5 only] added "widgets" option to relevant project files (not compiling UI on Qt5)
* [qt5 only] removed Application::setGraphicsSystem call (not supported on Qt5)
* [qt5 only] replaced QDesktopServices::storageLocation(QDesktopServices::HomeLocation) with QDir::homePath() (not supported on Qt5)
* [qt5 only] replaced setResizeMode with setSectionResizeMode (not supported on Qt5)
* [global] replaced toAscii() with toLatin1() (not supported on Qt5)
* [global] replaced setPixmap(NULL) with clear() (compilation error on gcc)

There is also a problem with included libraries:
- qatemcontrol is compiled against qt4 - I think that two versions should be included or maybe source code,
- libvlc has gui/libqt4_plugin compiled against qt4 - I think it is not used so it can probably be safely removed.

Tested with Qt 5.2.1 and GCC 4.8.2 on Kubuntu 14.04.