updated libraries

[Luiz Henrique de Figueiredo <lhf@...>]

I've updated some of my libraries (lgdbm, lmd5, lrandom, luuid). The update
includes cleaner code and some extra functionality. The READMEs have been
simplified and detailed installation instructions are now at a single place:
	http://www.tecgraf.puc-rio.br/~lhf/ftp/lua/install.html

I hope this makes it easier to use my libraries.

I plan to write a separate page that describing the design of my bindings,
specially the userdata and methods issue.

All comments are welcome. Enjoy.
--lhf