Hi, the attached patch changes the translated manual name, from e.g.
guix.fr to guix-fr. The reason is that some info readers and generators
drop everything after the first dot to get the name of the manual. This
leads some readers to thing that "info guix" should open "guix.es.info"
instead of "guix.info", and the inter-lingua links on the website
version of the manual to be wrong.

I think I replaced every instance of the filename in this patch, but I
might have forgotten some, so if you see anything I missed, please tell
me :)