Update uuid module on github.com/arcapos/luauuid

[Marc Balmer <marc@...>]

libuuid is a library found on most Linux systems to deal with "Universally Unique Identifiers" or UUIDs in short.

A lua binding for it can be found at https://github.com/arcapos/luauuid/.

I just updated the repository, which existed already for some time, with proper documentation in AsciiDoc format.

- mb