add flake8 config

setup.cfg

@@ -5,3 +5,7 @@ with-doctest=1
 [bdist_wheel]
 # This flag says that the code is written to work on both Python 2 and Python 3.
 universal=1
+
+[flake8]
+exclude = .git,.tox,.github,.eggs,__pycache__,doc/conf.py,build,dist,capabilities-data,test
+max-line-length = 100