DEP: deprecate float as axis argument to reductions

consistent with deprecation of float as slice indices.
Closes gh-4876
BUG Make ma[row][rec] setter work by avoiding copy in mvoid.__new__
BUG: core: fix crash when unpickling data on Py3 under non-latin1 encoding
BUG: initialize object array of array on resize and zeros

np.zeros(2, dtype=[('k', object, 2)]) did only initialize the first
element to zero while the rest stayed None.

    In [1]: numpy.zeros(2, dtype=[('k', object, 2)])
    Out[1]:
    array([([0, None],), ([0, None],)],
          dtype=[('k', 'O', (2,))])

This is a surprising and likely not intended behavior which is fixed
here.
The changed function PyArray_FillObjectArray is only used with None or
zero inputs from numpy, though as its part of the API it could affect
third parties but this is not very likely.

Additionally the memory after the first element was not initialized when
the object was resized.
Closes gh-4857
Merge pull request #4891 from juliantaylor/reduce-float-axis

DEP: deprecate float as axis argument to reductions, for 1.9
Merge pull request #4882 from pv/fix-unpickle-latin1-crash

BUG: core: fix crash when unpickling data on Py3 under non-latin1 encoding
ENH: core: add hack enabling unpickling Py2 pickled scalars on Py3 under encoding='latin1'

There is a similar hack in place for arrays, but scalar unpickling was not covered.

Provides a workaround for gh-4879
Merge pull request #4883 from pv/fix-scalar-unpickle-py3

ENH: core: add hack enabling unpickling Py2 pickled scalars on Py3 under encoding='latin1'
BLD: fix build issues with MSVC10 on Windows.  Closes gh-4245.

Note that there are a few similar patches posted to gh-4101 and gh-4245.
Those were all patches to msvc9compiler in Python distutils.
Monkeypatching ``MSVCCompiler.link`` is less easy than this change
to ``config._check_compiler``; effect should be the same.

Also updates the error message shown when initializing MSVC fails.

[ci skip]
Merge pull request #4892 from rgommers/msvc10-fix

BLD: fix build issues with MSVC10 on Windows.  Closes gh-4245.
ENH: core: make unpickling with encoding='bytes' work

Make dtype.__setstate__ accept endian either as a byte string or unicode.

Also fix a missing error return introduced in c3551579, apparently
mistake.
BUG: core: ensure unpickled dtype fields and names have correct types + coerce on Py3

That 'names' is a tuple and 'fields' a dict (when present) is assumed in
most of the code base, so check them during unpickling.

Also add coercion from bytes using ASCII codec on Python 3.  This is
never triggered in the "usual" case of loading Py3-generated pickles on
Py3, but can occur if loading Py2 generated pickles with
pickle.load(f, encoding='bytes'), which sometimes is the only working
option.

The ASCII codec is probably the safest choice and likely covers most use
cases.
Merge pull request #4888 from pv/fix-bytes-encoding-unpickle

ENH: core: make unpickling with encoding='bytes' work
Merge pull request #4889 from juliantaylor/object-array-init

BUG: initialize object array of array on resize and zeros
Merge pull request #4866 from mhvk/ma/mvoid-initialisation

BUG Masked recarray assignment with [row][record] does not work
BUG: object array np.conjugate, ndarray.conjugate inconsistent

fixes gh-4730
Merge pull request #4887 from ewmoore/conj_obj

BUG: object array np.conjugate, ndarray.conjugate inconsistent
DOC: clarify that umfpack, fftw and djbfft are not used by numpy

their presence in site.cfg is only for the benefit of third party
packages using numpy.distutils
TST: win32 also does not provide 16 byte alignment

mingw builds set the alignment requirement for complex doubles types to
16 byte so the tests checking the alignment flag must be disabled.
Merge pull request #4908 from juliantaylor/win-alignment

TST: win32 also does not provide 16 byte alignment, for 1.9