* start using a private version of liolib.c. 
  (this will allow io.popen() intercepts, and means that
  lua51/liolib.c can revert back to the distributed one)

there was a bug in open_oslibext() that shielded it

and cleanup the open_oslibext() function.

there are super- or subscripts attached to the accentee

initialization of the needed variables via texmf.cnf or the texconfig table