* development/MacOSX/Makefile.am: when installing, create bogus
language directories to allow translation through Qt.
* src/frontends/qt4/GuiApplication.cpp (MenuTranslator): new class,
redirects some Qt translation requests to gettext.
(GuiApplication): install the MenuTranslator.
git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/trunk@19354 a592a061-630c-0410-9148-cb99ea01b6c8