Add support for using openblas for the _dotblas function.
BLD: Update with information about openblas.
DOC: hfft/ihfft description conflicts with itself

Says Hermite spectrum when it means signal
DOC: Add examples, copy some text from rfft functions to clarify inputs and outputs
DOC: add note clarifying why ifftshift is needed
BUG: Set __hash__ = None for non-hashable classes.

Because neither poly1d nor the Polynomial package polynomial classes are
immutable, hence not reliably hashable, they should signal that by
setting __hash__ = None. This also fixes the warning

Overriding __eq__ blocks inheritance of __hash__ in 3.x

that is given when the command `python2.7 -3 -c"import numpy"` is run.
ENH: Avoiding conversion of integer to NumPy Scalar.
There is a bottleneck in scalar operations, when trying to extract the
underlying C value from a Python integer/float. I have avoid conversion
for know integer type but extracting its value.
Extracting longlong value without converting it to NyType
Moved int test cases to pr#3592
Added PyInt_CheckExact for python < 3 and error check for PyLong_AsLong
Replaced PyInt_As_Long with PyInt_AsLong and  errorchecking
DOC: change "Hermite" to "Hermitian", "though" to "although"
DOC: Remove parentheses around axis
DOC: Unlink non-variable 'm', use monospace instead
Merge pull request #3647 from endolith/patch-1

DOC: hfft/ihfft description conflicts with itself
ENH: add nonzero of bools fastpath

count_nonzero already has a fastpath but nonzero does not.
Improves performance by about 25% via avoiding a function call.
Merge pull request #3644 from juliantaylor/nonzero-bool

ENH: add nonzero of bools fastpath
Check for error value by PyLong_AsUnsignedLong as (unsigned long)-1
DOC: Add NEP and documentation for ufunc overrides.
ENH: Add ufunc override API.