ValueError exception with pd.resample
When running `df.resample('2200L', how='sum', label='right')` with `df`:

```
2014-10-14 23:06:07.440000    6.44000
2014-10-14 23:06:07.761000    5.09600
2014-10-14 23:06:08.215000    6.44000
2014-10-14 23:06:08.486000    6.44000
2014-10-14 23:06:08.509000    5.20800
2014-10-14 23:06:08.789000    4.02842
2014-10-14 23:06:10.795000    5.65600
2014-10-14 23:06:11.618000    6.21600
2014-10-14 23:06:12.177000    6.21600
2014-10-14 23:06:14.620000    5.10720
2014-10-14 23:06:16.698000    5.95840
2014-10-14 23:06:16.745000    6.44000
2014-10-14 23:06:20.548000    6.21600
2014-10-14 23:06:20.549000    6.44000
2014-10-14 23:06:20.551000    5.95840
2014-10-14 23:06:23.206000    6.44000
2014-10-14 23:06:29.977000    6.44000
2014-10-14 23:06:35.307000    5.20800
2014-10-15 23:00:00               NaN
2014-10-15 23:00:02.200000        NaN
Name: spend, dtype: float64
```

I got:

```
---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
<ipython-input-20-71895ab1ef27> in <module>()
----> 1 R_inst = loaded_sorted.tail(200).head(20).resample('2200L', how='sum', label='right')

/Users/josh/anaconda3/envs/py34/lib/python3.4/site-packages/pandas/core/generic.py in resample(self, rule, how, axis, fill_method, closed, label, convention, kind, 
loffset, limit, base)                                                                                                                                                  
   2978                               fill_method=fill_method, convention=convention,
   2979                               limit=limit, base=base)
-> 2980         return sampler.resample(self).__finalize__(self)
   2981 
   2982     def first(self, offset):

/Users/josh/anaconda3/envs/py34/lib/python3.4/site-packages/pandas/tseries/resample.py in resample(self, obj)
     83 
     84         if isinstance(ax, DatetimeIndex):
---> 85             rs = self._resample_timestamps()
     86         elif isinstance(ax, PeriodIndex):
     87             offset = to_offset(self.freq)

/Users/josh/anaconda3/envs/py34/lib/python3.4/site-packages/pandas/tseries/resample.py in _resample_timestamps(self, kind)
    273         axlabels = self.ax
    274 
--> 275         self._get_binner_for_resample(kind=kind)
    276         grouper = self.grouper
    277         binner = self.binner

/Users/josh/anaconda3/envs/py34/lib/python3.4/site-packages/pandas/tseries/resample.py in _get_binner_for_resample(self, kind)
    121             kind = self.kind
    122         if kind is None or kind == 'timestamp':
--> 123             self.binner, bins, binlabels = self._get_time_bins(ax)
    124         elif kind == 'timedelta':
    125             self.binner, bins, binlabels = self._get_time_delta_bins(ax)

/Users/josh/anaconda3/envs/py34/lib/python3.4/site-packages/pandas/tseries/resample.py in _get_time_bins(self, ax)
    182 
    183         # general version, knowing nothing about relative frequencies
--> 184         bins = lib.generate_bins_dt64(ax_values, bin_edges, self.closed, hasnans=ax.hasnans)
    185 
    186         if self.closed == 'right':

/Users/josh/anaconda3/envs/py34/lib/python3.4/site-packages/pandas/lib.so in pandas.lib.generate_bins_dt64 (pandas/lib.c:17928)()

ValueError: Values falls after last bin
```

with `Python 3.4.1 :: Anaconda 2.1.0 (x86_64)` and:

```
Cython==0.21
DataShape==0.3.0
Flask==0.10.1
Jinja2==2.7.3
MarkupSafe==0.23
Pillow==2.5.1
PyYAML==3.11
Pygments==1.6
SQLAlchemy==0.9.7
Sphinx==1.2.3
Theano==0.6.0
Werkzeug==0.9.6
XlsxWriter==0.5.7
abstract-rendering==0.5.1
appnope==0.1.0
argcomplete==0.8.1
arrow==0.4.4
astropy==0.4.2
beautifulsoup4==4.3.2
binstar==0.7.1
bitarray==0.8.1
blaze==0.6.3
blz==0.6.2
bokeh==0.6.1
boto==2.34.0
cffi==0.8.6
colorama==0.3.1
configobj==5.0.6
cryptography==0.5.4
cytoolz==0.7.0
decorator==3.4.0
docutils==0.12
future==0.13.1
greenlet==0.4.4
h5py==2.3.1
ipython==2.2.0
itsdangerous==0.24
jdcal==1.0
jedi==0.8.1-final0
## FIXME: could not find svn URL in dependency_links for this package:
joblib==0.8.3-r1
llvmpy==0.12.7
lpsolve55==5.5.2.0
lxml==3.4.0
matplotlib==1.4.0
mock==1.0.1
multipledispatch==0.4.7
networkx==1.9.1
nltk==3.0.0
nose==1.3.4
numba==0.14.0
numexpr==2.3.1
numpy==1.9.0
openpyxl==1.8.5
pandas==0.15.0
parse==1.6.4
patsy==0.3.0
ply==3.4
psutil==2.1.1
psycopg2==2.5.4
py==1.4.25
pyOpenSSL==0.14
pycosat==0.6.1
pycparser==2.10
pycrypto==2.6.1
pycurl==7.19.5
pyflakes==0.8.1
pymc==3.0
pyparsing==2.0.1
pytest==2.6.3
python-dateutil==2.1
pytz==2014.7
pyzmq==14.3.1
qds-sdk==1.2.2
redis==2.9.1
requests==2.4.3
rope-py3k==0.9.4-1
runipy==0.1.1
scikit-image==0.10.1
scikit-learn==0.15.2
scipy==0.14.0
seaborn==0.5.dev
six==1.8.0
sockjs-tornado==1.0.1
spyder==2.3.1
statsmodels==0.5.0
sympy==0.7.5
tables==3.1.1
toolz==0.7.0
tornado==4.0.2
ujson==1.33
xlrd==0.9.3
```
