COMPAT: numpy master changes, floordiv & getitem(nan)
https://travis-ci.org/pydata/pandas/jobs/110280302

These indicate an indexing change with `nan` that now returns `TypeError` rather than `IndexError`, ok makes sense

```
======================================================================
ERROR: test_range_slice_day (pandas.tseries.tests.test_period.TestPeriodIndex)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/jreback/miniconda/envs/numpy_dev/pandas/pandas/tseries/tests/test_period.py", line 2589, in test_range_slice_day
    idx[v:]
  File "/Users/jreback/miniconda/envs/numpy_dev/pandas/pandas/tseries/base.py", line 175, in __getitem__
    result = getitem(key)
TypeError: slice indices must be integers or None or have an __index__ method

======================================================================
ERROR: test_range_slice_seconds (pandas.tseries.tests.test_period.TestPeriodIndex)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/jreback/miniconda/envs/numpy_dev/pandas/pandas/tseries/tests/test_period.py", line 2643, in test_range_slice_seconds
    idx[v:]
  File "/Users/jreback/miniconda/envs/numpy_dev/pandas/pandas/tseries/base.py", line 175, in __getitem__
    result = getitem(key)
TypeError: slice indices must be integers or None or have an __index__ method
```

So our comparison in this test changed. So we need to make this change for 0.18.0 as well [here](https://github.com/pydata/pandas/blob/master/pandas/src/sparse.pyx#L1002), where these should be `NaN` and not `inf`.

```
So numpy now returns:
In [1]: np.__version__
Out[1]: '1.12.0.dev0+7d4d26a'

In [3]: np.array([3])//np.array([0],dtype='float64')
Out[3]: array([ nan])

In [2]: np.float64(3)//np.float64(0)
Out[2]: nan

In [3]: np.__version__
Out[3]: '1.10.4'

In [4]: np.float64(3)//np.float64(0)
Out[4]: inf

In [7]: np.array([3])//np.array([0],dtype='float64')
Out[7]: array([ inf])
```

```
======================================================================
FAIL: test_sparse_series_ops (pandas.sparse.tests.test_sparse.TestSparseDataFrame)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/jreback/miniconda/envs/numpy_dev/pandas/pandas/sparse/tests/test_sparse.py", line 1151, in test_sparse_series_ops
    self._check_frame_ops(self.frame)
  File "/Users/jreback/miniconda/envs/numpy_dev/pandas/pandas/sparse/tests/test_sparse.py", line 1221, in _check_frame_ops
    _compare_to_dense(frame, s, frame.to_dense(), s.to_dense(), f)
  File "/Users/jreback/miniconda/envs/numpy_dev/pandas/pandas/sparse/tests/test_sparse.py", line 1194, in _compare_to_dense
    exact_indices=False)
  File "/Users/jreback/miniconda/envs/numpy_dev/pandas/pandas/sparse/tests/test_sparse.py", line 95, in assert_sp_frame_equal
    assert_series_equal(series.to_dense(), right[col].to_dense())
  File "/Users/jreback/miniconda/envs/numpy_dev/pandas/pandas/util/testing.py", line 999, in assert_series_equal
    check_less_precise, obj='{0}'.format(obj))
  File "testing.pyx", line 58, in pandas._testing.assert_almost_equal (pandas/src/testing.c:3254)
  File "testing.pyx", line 147, in pandas._testing.assert_almost_equal (pandas/src/testing.c:2395)
  File "/Users/jreback/miniconda/envs/numpy_dev/pandas/pandas/util/testing.py", line 867, in raise_assert_detail
    raise AssertionError(msg)
AssertionError: Series are different

Series values are different (10.0 %)
[left]:  [nan, nan, nan, inf, 4.0, 2.0, 2.0, 1.0, 1.0, 1.0]
[right]: [nan, nan, nan, nan, 4.0, 2.0, 2.0, 1.0, 1.0, 1.0]
```
