Workaround for the problem that *.gmo files are not updated
    
    For some reasons (*.gmo and probably some more files present in the
    tarball) the make scripts think that *.gmo files do not need to be
    rebuilt even if we have and apply some patches that update the *.po
    files. As a result, the updated translations are never visible in the
    final binary package. For now we don't have a better solution than
    force the rebuild explicitly.