use abi3 extension if Extension().is_abi3

Fix spacing after comment hash.

Add missing whitespace after comma.

Add tests for MANIFEST.in

numpy.distutils and distutils._msvccompiler compatibility

Upgrade pyparsing to version 2.1.8

Fix comparison with None.

Fix spacing after comment hash.

Add missing whitespace around operators.

Remove whitespace around parameter = sign.

Agree with @pitrou comment.

- Fix compatibility between `numpy.distutils` and `distutils._msvccompiler`. See #728 : Setuptools 24 `msvc.py` improvement import `distutils._msvccompiler` (New Python 3.5 C compiler for MSVC >= 14), but this one is not compatible with `numpy.distutils` (because not patched with `numpy.distutils.ccompiler.gen_lib_options`) and return unquoted libpaths when linking. The problem was patched in Numpy, but need to be patched also in Setuptools for compatibility between older versions of Numpy and `distutils._msvccompiler` (and indirectly Setuptools > 24).
- Replace some residuals `except Exception`.

Bundle the license

Update tox.ini envlist to match supported Pythons