sync with current luatex-mplib as of 2013-05-07
keep % as comment char
import Kim’s patch to luatex-mplib.lua
import Kim’s patch to luatex-mplib.tex
fix missing upvalues
use mplib catcodes for both Latex and Plain
Fixing minor errors
Add test file for LaTeX
Using luatexbase info, log and err
A few more locals
Update doc style and Makefile (pdflatex -> lualatex)
Minor dtx fix
Minor doc update
GPLv2 instead of CC0
Readme update
Document changes by Kim in the context code
Removing dead code from the old environment
Adding a test in plain too
Adding a little more doc
Remove unneccessary dependencies