test_bar_log fights back with matplotlib 1.3.0
```
======================================================================
FAIL: test_bar_log (pandas.tests.test_graphics.TestDataFramePlots)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/yoh/deb/gits/pkg-exppsy/pandas/pandas/tests/test_graphics.py", line 568, in test_bar_log
    self.assertEqual(ax.yaxis.get_ticklocs()[0], 1.0)
AssertionError: 0.10000000000000001 != 1.0

----------------------------------------------------------------------
Ran 1 test in 0.341s
```

needs to be fixed up for debian where mpl now 1.3.0
