[Lint] Use Black to auto-format code

The move to using auto-formatter makes it easier to read, submit and
speeds up development time. https://github.com/ambv/black/

Although I would prefer 79 chars, the default line length of 88 chars
used by black suffices. The flake8 line length remains at 120 chars
since black does not touch comments or docstrings and this will require
another round of fixes.

The only black setting that is not standard is the use of double-quotes
for strings so disabled any formatting of these. Note however that
flake8 will still flag usage of double-quotes. I may change my mind on
double vs single quotes but for now leave them.

A new pyproject.toml file has been created for black configuration.

1 files changed, 0 insertions, 15 deletions

diff --git a/tox.ini b/tox.ini
index 52626d3e2..3e4b05a7e 100644
--- a/tox.ini
+++ b/tox.ini
@@ -3,21 +3,6 @@
 #
 # Usage: `pip install tox` and then run `tox` from this directory.
 
-[flake8]
-max-line-length = 120
-builtins = _,_n,__request__
-exclude = .git,.tox,dist,build
-ignore =
-# A003 Class attribute is a python builtin.
-    A003,
-# C813, C815, C816: PY3 missing trailing commas.
-    C813,C815,C816,
-# W503 line break before binary operator.
-    W503,
-
-[pycodestyle]
-max-line-length = 120
-
 [tox]
 envlist = py27, flake8, docs
 minversion=2.0