Fix file system location of localization file.

From: Lucio Sauer <watermanpaint@posteo.net>
--- a/extras/qt-tray/main.cpp
+++ b/extras/qt-tray/main.cpp
@@ -30,7 +30,8 @@ int main(int argc, char *argv[])
     QTranslator translator(0);
 
 
-    translator.load( QString("./i18n/tomb-qt-tray_") + QLocale::system().name() );
+    translator.load( QString("tomb-qt-tray_it"),
+		     "@GENTOO_PORTAGE_EPREFIX@/usr/share/locale/it_IT/LC_MESSAGES");
 
     a.installTranslator( &translator );
     //w.show();