* It appeared that many po/POTFILES.in files were totally out of date...
Updated those accordingly, and translated the new strings.
NB: Does anyone would object to a modification of po/Makefile.in.in files to
generate automatically the POTFILES.in's with a cmd like:
grep '_(' `find . -name \*.\[chym\]` | cut -f 1 --delimiter ':' | sed -e "s#^./##" |sort -u > po/POTFILES.in
4dc80d85c6