rather than just complaining about stderr not being what we expected masking
the true problem.

Fix segfault discovered by Ron Adam.  Not checking for terminating right bracket in "'{0[}'.format(())".  Fixed, and tests added.

Removed used_args param from string.Formatter.get_field.  It was left in by mistake from an earlier edit.

Partial py3k-ification of Doc/library/: convert has_key references into either 'k in d' or __contains__; normalize raise statements; convert print statements into print function calls.

- throw out many mentions of "old-style/new-style"
- add memoryview() though I somebody has to fill in the details
- throw out str.decode()
- throw out classobj and instanceobj