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: Add paver generated release directory to .gitignore.
Merge pull request #3674 from charris/add-to-gitignore

ENH: Add paver generated release directory to .gitignore.
STY: Make numpy/lib/test/*.py PEP8 compliant.

Run autopep8 over the test files in numpy/lib/test and make fixes
to the result.

Also remove Python5 workaround.
Revert "Merge pull request #3567 from arinkverma/avoid_conversion"

This reverts commit de9f1c92d3ca0920bce915438f0406f587aa98db, reversing
changes made to d958dec676beeac218a118fac084fa8b14bc9171.

There is a change of behavior in conversion of signed to unsigned
PyLong that shows up on my machine. For some reason this did not show
up in the travisbot tests. This reverts the merge that led to this
problem until it can be sorted out. Error shows up as

numpy/core/arrayprint.py",
line 653, in __call__
    if _MININT < x < _MAXINT:
OverflowError: can't convert negative int to unsigned
Merge pull request #3675 from charris/revert-merge-pr-3567

Revert "Merge pull request #3567 from arinkverma/avoid_conversion"
Merge pull request #3673 from charris/pep8-lib-tests

STY: Make numpy/lib/test/*.py PEP8 compliant.
BUG: PyArray_PyIntAsIntp had variable size check wrong way around.

This bug resulted in using a long type when a long long was required,
resulting in numerous errors when numpy was compiled as 64 bits on
64 bit windows.
Merge pull request #3678 from charris/fix-wrong-variable-type

BUG: PyArray_PyIntAsIntp had variable size check wrong way around.
Merge pull request #3657 from charris/add-hash-method-to-polynomials

BUG: Set __hash__ = None for non-hashable classes.