additional (failing) tests for dict

[R. David Murray]

Played with pynie after the pycon talk (nice talk), and noticed that the (very new!) dict support has a few issues :). Here are a couple of tests for things I noticed.

[Allison Randal (allison)]

Thanks, these are great! I've committed the test with the fixes to make it pass.

One of the tests didn't work in Python 3 (I found an explanation in http://blog.labix.org/2008/06/27/watch-out-for-listdictkeys-in-python-3):

Traceback (most recent call last):
  File "Lib/test/bootstrap/dicts.py", line 25, in <module>
    if a.keys()[0] == 1: print('success: integer as index')
TypeError: 'dict_keys' object does not support indexing

So I tweaked that test to:

a = {1: 2}
b = list(a.keys())
if b[0] == 1: print('success: integer as index')

Thanks for the contribution!