Add Qt own translation files for version 4.8.5 to be able to translate all base texts. These files are not listed in goldendict.pro file because doing that would mean that every time we call lupdate goldendict.pro all texts would be marked as obsolete because they are not part of GoldenDict codebase. The same thing (and for the same reason) would happen if we add only the needed text from qt_*.ts to Goldendict's own translation files. So we have to find a way to be able to generate the qt_*.qm files during the build and deploy phases.