Tag translations correctly with %find_lang.
Re-run intltoolize to regenerate po/Makefile.in.in after autoreconf. The first
intltoolize run makes sure that appropriate intltool.m4 is in place before
autoreconf.
In case autoconf generates configure withouth the new intltool.m4 DATADIRNAME
is not substituted into po/Makefile.in and translations are not installed.