BLD: numpy-dev causing some issues

[jreback]

https://travis-ci.org/pandas-dev/pandas/jobs/194558937

numpy/numpy#8279 was just merged, which broke our tests

:>

[jreback]

cc @jcrist

[jcrist]

Looks like the issue is this line: https://github.com/pandas-dev/pandas/blob/master/pandas/core/ops.py#L453.

Before that numpy PR, that would always evaluate lib.infer_dtype, since bool(scalar_dtype) was always False.

[jreback]

yep, going to put a patch in shortly.