tokenizer.c: make coding markup work again. io.open() now takes all positional parameters (so we can conveniently call it from C code). test_tarfile.py no longer uses u"..." literals, but is otherwise still badly broken. This is a checkpoint; some more stuff now breaks.

/* This module provides the necessary stubs for when dynamic loading is
   not present. */

#include "Python.h"
#include "importdl.h"


const struct filedescr _PyImport_DynLoadFiletab[] = {
	{0, 0}
};