test failures and errors with v0.11rc1
I get one failure and 7 errors when I run the test suite on v0.11rc1.

This is the traceback of the error:

``` ======================================================================
FAIL: testWLS (pandas.stats.tests.test_ols.TestOLS)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/.../pandas/pandas/stats/tests/test_ols.py", line 107, in testWLS
    self._check_wls(X, Y, weights)
  File "/.../pandas/pandas/stats/tests/test_ols.py", line 130, in _check_wls
    self.checkMovingOLS('rolling', x, y, weights=weights)
  File "/.../pandas/pandas/stats/tests/test_ols.py", line 204, in checkMovingOLS
    result_index=n)
  File "/.../pandas/pandas/stats/tests/test_ols.py", line 243, in compare
    assert_almost_equal(ref, res)
  File "/.../pandas/pandas/util/testing.py", line 139, in assert_almost_equal
    assert_almost_equal(a[i], b[i], check_less_precise)
  File "/.../pandas/pandas/util/testing.py", line 170, in assert_almost_equal
    1, a / b, decimal=decimal, err_msg=err_msg(a, b), verbose=False)
  File "/.../python2.7/site-packages/numpy/testing/utils.py", line 468, in assert_almost_equal
    raise AssertionError(msg)
AssertionError: 
Arrays are not almost equal to 5 decimals expected 1.62656 but got 1.62097
```

For `test_axis_limits`, `test_line_plot_datetime_frame`,
`test_line_plot_datetime_series`, `test_line_plot_inferred_freq`, `test_line_plot_period_frame`, 
`test_line_plot_period_series` and `test_tsplot` I get a `ValueError`:

```
ValueError: matplotlib display text must have all code points < 128 or use Unicode strings
```

The reason for the errors seems to be my language setting, which is `de_DE.UTF-8`. I never got these errors in the pandas test suite before so maybe they are also related to the recent update to matplotlib 1.2.1.

```
print_versions.py 

INSTALLED VERSIONS
------------------
Python: 2.7.4.final.0
Cython: 0.18
Numpy: 1.7.1
Scipy: 0.12.0
statsmodels: 0.5.0.dev-1bbd4ca
    patsy: 0.1.0
scikits.timeseries: Not installed
dateutil: 2.1
pytz: 2013b
PyTables: 2.4.0
    numexpr: 2.0.1
matplotlib: 1.2.1
openpyxl: Not installed
xlrd: Not installed
xlwt: 0.7.4
sqlalchemy: 0.8.0
```
