FE/Qt: language string updates.
FE/Qt4-OSX: fix the translation of the application menu
FE/Qt4-NLS: merged ca, ca_VA, ja, zh_TW, nl, pl, it, bg, cs, ko and pt_BR
FE/Qt4-NLS: updated qt_* translation files to 4.4.3
renamed VirtualBox4 to VirtualBox
purge the obsolete Qt3 GUI
FE/Qt: Japanese Qt translation update.
FE/Qt: Updated Japanese, Spanish, French, Polish, Romanian, Russian and Chinese (Taiwan) translations. All other translations were synchronized with sources.
FE/Qt: Added Japanese translation.