TST: comparison vs timezone issue for current pytz
Test just needs to use a localized version in the comparison

```
FAIL: test_with_tz (pandas.tseries.tests.test_timezones.TestTimeZoneSupportPytz)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/travis/virtualenv/python3.4.0/lib/python3.4/site-packages/pandas/tseries/tests/test_timezones.py", line 406, in test_with_tz
    self.assertIs(central[0].tz, tz)
  File "/home/travis/virtualenv/python3.4.0/lib/python3.4/site-packages/pandas/util/testing.py", line 96, in assertIs
    assert a is b, "%s: %r is not %r" % (msg.format(a,b), a, b)
AssertionError: : <DstTzInfo 'US/Central' CST-1 day, 18:00:00 STD> is not <DstTzInfo 'US/Central' LMT-1 day, 18:09:00 STD>
----------------------------------------------------------------------
Ran 7104 tests in 558.494s

```

 https://travis-ci.org/pydata/pandas/jobs/26755161
