configure flake8

Author: graingert

setup.cfg

@@ -3,3 +3,9 @@
 # 3. If at all possible, it is good practice to do this. If you cannot, you
 # will need to generate wheels for each Python version that you support.
 universal=1
+
+[flake8]
+disable-noqa = True
+max-line-length = 88
+extend-ignore =
+   E203,  # whitespace before : is not PEP8 compliant (& conflicts with black)