ValueError plotting bar plot from DataFrame with existing Axes
#### Code Sample, a copy-pastable example if possible

The following code works, and when pasted in a Jupyter Notebook or QT console yields the expected bar plot:

``` python
%matplotlib inline
import pandas as pd
import matplotlib.pyplot as plt

# Create some data to plot
df = pd.DataFrame(
        dict(Feature1=[10, 20, 30, 20, 10], Feature2=[3, 2, 3, 2, 3]),
        index=['a', 'b', 'c', 'd', 'e']
)
_ = df.plot(kind='bar', legend=False, y='Feature1', yerr='Feature2', rot=0)
```

However, as soon as I try to supply a custom `Axes` instance (so the plot gets put where I want it), it throws an error.  Running the following code after the above example throws an error:

``` python
fig = plt.figure(0)
ax = fig.add_subplot(111)
_ = df.plot(kind='bar', legend=False, y='Feature1', yerr='Feature2', rot=0, axes=ax)
```

Here is the traceback:

```
Traceback (most recent call last):
  File "<stdin>", line 12, in <module>
  File "/usr/local/miniconda3/lib/python3.5/site-packages/pandas/tools/plotting.py", line 3740, in __call__
    sort_columns=sort_columns, **kwds)
  File "/usr/local/miniconda3/lib/python3.5/site-packages/pandas/tools/plotting.py", line 2614, in plot_frame
    **kwds)
  File "/usr/local/miniconda3/lib/python3.5/site-packages/pandas/tools/plotting.py", line 2441, in _plot
    plot_obj.generate()
  File "/usr/local/miniconda3/lib/python3.5/site-packages/pandas/tools/plotting.py", line 1028, in generate
    self._make_plot()
  File "/usr/local/miniconda3/lib/python3.5/site-packages/pandas/tools/plotting.py", line 1971, in _make_plot
    log=self.log, **kwds)
  File "/usr/local/miniconda3/lib/python3.5/site-packages/pandas/tools/plotting.py", line 1918, in _plot
    return ax.bar(x, y, w, bottom=start, log=log, **kwds)
  File "/usr/local/miniconda3/lib/python3.5/site-packages/matplotlib/__init__.py", line 1812, in inner
    return func(ax, *args, **kwargs)
  File "/usr/local/miniconda3/lib/python3.5/site-packages/matplotlib/axes/_axes.py", line 2134, in bar
    self.add_patch(r)
  File "/usr/local/miniconda3/lib/python3.5/site-packages/matplotlib/axes/_base.py", line 1780, in add_patch
    self._set_artist_props(p)
  File "/usr/local/miniconda3/lib/python3.5/site-packages/matplotlib/axes/_base.py", line 865, in _set_artist_props
    a.axes = self
  File "/usr/local/miniconda3/lib/python3.5/site-packages/matplotlib/artist.py", line 237, in axes
    raise ValueError("Can not reset the axes.  You are "
ValueError: Can not reset the axes.  You are probably trying to re-use an artist in more than one Axes which is not supported
```
#### Expected Output

I would expect the second plot to work identically to the first plot in this example.
#### output of `pd.show_versions()`

```
INSTALLED VERSIONS
------------------
commit: None
python: 3.5.2.final.0
python-bits: 64
OS: Linux
OS-release: 4.4.6-gentoo
machine: x86_64
processor: Intel(R) Core(TM) i3-3240 CPU @ 3.40GHz
byteorder: little
LC_ALL: None
LANG: en_US.utf8

pandas: 0.18.1
nose: 1.3.7
pip: 8.1.2
setuptools: 25.1.6
Cython: None
numpy: 1.11.1
scipy: 0.18.0
statsmodels: 0.6.1
xarray: None
IPython: 5.1.0
sphinx: 1.4.1
patsy: 0.4.1
dateutil: 2.5.3
pytz: 2016.6.1
blosc: None
bottleneck: None
tables: 3.2.3.1
numexpr: 2.6.1
matplotlib: 1.5.1
openpyxl: None
xlrd: 1.0.0
xlwt: None
xlsxwriter: None
lxml: None
bs4: None
html5lib: None
httplib2: None
apiclient: None
sqlalchemy: 1.0.13
pymysql: None
psycopg2: 2.6.1 (dt dec pq3 ext)
jinja2: 2.8
boto: None
pandas_datareader: None
```

(FWIW, I just built and tried the latest version of pandas and got the same behavior:

```
pandas: 0.18.1+391.g6645b2b
```

)
