Add Lua-based make files for l3experimental

This is mainly to check that the system extends readily to other diretories:
all looks good so far.

Note that:
 - One of the test files fails as the Lua script does not strip out the lvt name
   from the processed log - that's deliberate and I think reasonable
 - I've not added any of the example files to the set that go to CTAN, but
   perhaps some of these should


git-svn-id: http://www.latex-project.org/svnroot/experimental/trunk@4773 de43f980-851b-0410-b2f7-c40aca1f87e0