TST: test_boxplot failures
These are failing for me on master

```
nosetests test_graphics:TestDataFramePlots.test_boxplot test_graphics:TestDataFramePlots.test_boxplot_vertical
FF
======================================================================
FAIL: test_boxplot (test_graphics.TestDataFramePlots)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/tom/Envs/py3/lib/python3.4/site-packages/pandas/pandas/tests/test_graphics.py", line 1736, in test_boxplot
    self.assertEqual(len(ax.lines), 8 * len(numeric_cols))
AssertionError: 21 != 24

======================================================================
FAIL: test_boxplot_vertical (test_graphics.TestDataFramePlots)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/tom/Envs/py3/lib/python3.4/site-packages/pandas/pandas/tests/test_graphics.py", line 1770, in test_boxplot_vertical
    self.assertEqual(len(ax.lines), 8 * len(numeric_cols))
AssertionError: 21 != 24

----------------------------------------------------------------------
Ran 2 tests in 0.659s

FAILED (failures=2)
```

``` python
In [1]: pd.__version__
Out[1]: '0.14.1-445-g83ff5b1'
```

Will look later.
