FE/Qt: language string updates.
FE/Qt4-OSX: fix the translation of the application menu
FE/Qt4-NLS: updated qt_* translation files to 4.4.3
FE/Qt-NLS: Updated Slovak, Czech, Hungarian, Romanian, Turkish, Finnish, Catalan, Italian, Swedish translation files.
renamed VirtualBox4 to VirtualBox
purge the obsolete Qt3 GUI
FE/Qt: Updated Romanian, Spanish, French, Japanese translations to 1.4.0; added Brasilian Portugese translation.
FE/Qt: Updated Russian, Romanian and French languages.
FE/Qt: Romanian language update.
FE/Qt: Added Qt translation sources from the Qt distribution; created untranslated sources for existing languages; added code to load Qt translations on language change.