[gfsd]Lua entry

[Luiz Henrique de Figueiredo]

Thanks for adding Lua to the GNU Free Software Directory.
Some comments:

- The name is "Lua" not "lua" in http://www.gnu.org/directory/listing.html
- Lua does not appear in http://www.gnu.org/directory/recent-additions.html
- No match is found for Lua in the Search facility.

Thanks again.
--lhf