Adding support of ppc64le architecture

Signed-off-by: William Grant <wgrant@ubuntu.com>
Signed-off-by: Michel Normand <normand@linux.vnet.ibm.com>
BUG: Ensure MaskedArray.flat can access single items
BLD: remove cython c source from git

Instead generate at build time. The generated sources are still part of
the sdist.
tools/cythonize.py is copied from SciPy with small changes to the
configuration.
ENH: Better error w/ line num for bad column count in np.loadtxt()

Resolves #2591. Adds more explicit error handling in line parsing loop.
Merge pull request #4588 from ddasilva/ddasilva/2591

ENH: Better error w/ line num for bad column count in np.loadtxt()
BUG: Prevent division by zero. Closes #650.
Merge pull request #4591 from szpy/bugfixes

BUG: Prevent division by zero. Closes #650.
ENH: add a 'return_counts=' keyword argument to `np.unique`

This PR adds a new keyword argument to `np.unique` that returns the
number of times each unique item comes up in the array. This allows
replacing a typical numpy construct:

    unq, _ = np.unique(a, return_inverse=True)
    unq_counts = np.bincount(_)

with a single line of code:

    unq, unq_counts = np.unique(a, return_counts=True)

As a plus, it runs faster, because it does not need the extra
operations required to produce `unique_inverse`.
ENH: disable OpenBLAS affinity settings

OpenBLAS starts as many threads as it can and assigns them to cpus
This includes the main thread Python is running in.
This means any threads or processes Python starts must all share this
cpu, nullifying any parallization efforts.
Luckily this behaviour can be disabled via an environment variable which
we need to set before loading dotblas which may be linked to OpenBLAS.
Libraries loading BLAS before numpy are stills screwed.
BUG: ifort has issues with optimization flag /O2

Fixes scipy test failures.
Merge pull request #4602 from cgohlke/patch-2

BUG: ifort has issues with optimization flag /O2
Merge pull request #4589 from juliantaylor/cython-gen

BLD: remove cython c source from git
Merge pull request #4180 from jaimefrio/unique_counts

ENH: add a 'return_counts=' keyword argument to `np.unique`
Merge pull request #4551 from michelmno/master

ENH: adding ppc64le architecture support
Ensure single record items also work correctly with MaskedIterator; tests
Merge pull request #4585 from mhvk/ma/iterator-get-single-item

BUG: Ensure MaskedArray.flat can access single items
fixed bad signature in docstring for uniform()
BUG: Fix lack of NULL check in array_richcompare.

The lack of this check led to a segfault.

Closes #4613.
Merge pull request #4611 from gdementen/patch-1

fixed bad signature in docstring for uniform()
Merge pull request #4614 from charris/fix-gh-4613

BUG: Fix lack of NULL check in array_richcompare.