updated bc and mapm libraries

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

I've updated my big-number libraries for Lua 5.0:

	http://www.tecgraf.puc-rio.br/~lhf/ftp/lua/lbc.tar.gz
	http://www.tecgraf.puc-rio.br/~lhf/ftp/lua/lmapm.tar.gz
	ftp://ftp.tecgraf.puc-rio.br/pub/lhf/lua/lbc.tar.gz
	ftp://ftp.tecgraf.puc-rio.br/pub/lhf/lua/lmapm.tar.gz

I've cleaned up the binding and the support Lua code, and added better tests.
You need a Lua interpreter that has loadlib to run the tests, because the
Makefile creates shared libraries. It's the easiest way to test libraries
because you don't have to change or recompile lua.c.

The C bindings contain more functions than the versions for Lua 4.0,
which are still available at their original locations (search the
archives or see the wiki). It shouldn't be hard to adapt the new
libraries for Lua 4.0, because most of the code is binding code that
does not depend on Lua. If there is demand, perhaps I can do it when I
finish updating my other libraries (the POSIX library has priority).

Please send comments, suggestions, and bug reports direcly to me.
Enjoy.
--lhf