support both setuptools & distutils
Merge branch 'setuptools_v2' of github.com:mindw/uncertainties into mindw-setuptools_v2
Removed unnecessary comma.
Identical setup_options, but intermediate variables removed.
Typo fixed.
.gitignore adapted to PyCharm.
One more annovation in .gitignore.
setup.py is compatible with Python 3, now.
Merge branch 'mindw-setuptools_v2' (stylistic modifications made).