[Dev-luatex] lua library support

[Taco Hoekwater]

Hi,

I've committed a new version. This one has slnunicode embedded
and enabled, so this should work:

   \directlua0{  dofile("unitest") } % file is in slnunicode dir



Also, the luatex binary now exports its symbol table and links
with -ldl, so dynamic lua require's should also work:

   \directlua0{
    require "zip" % you need to have zip.so
    zfile = zip.open("cont-tmf.zip")
    for i,v in zfile:files() do
      tex.print (i.filename)
    end
    zfile:close()
}

For fp: sorry, even more linux-specific stuff in the makefiles.

This code is far from finished, I am just playing around trying
to figure out how to set it all up in a clean manner.

Cheers,
Taco