BUG: overflow in Timedelta arithmetic
xref https://github.com/pandas-dev/pandas/pull/17318#issuecomment-331594273

This is not behaving on master, started after: https://github.com/pandas-dev/pandas/commit/b59f107a529ac9b1e2859217ea58f7e26b6749d0
```
In [1]: date_range(start='1/1/1700', freq='B', periods=100000)
---------------------------------------------------------------------------
OverflowError                             Traceback (most recent call last)
OverflowError: Python int too large to convert to C long
Exception ignored in: 'pandas._libs.tslib._delta_to_nanoseconds'
OverflowError: Python int too large to convert to C long
Out[1]: DatetimeIndex(['1700-01-01', '1700-01-04', '1700-01-05', '1700-01-06', '1700-01-07'], dtype='datetime64[ns]', freq='B')

```