Code Linting / PEP8 cleanup / CI with Travis CI

[scls19fr]

Hello,

a PEP8 cleanup could be a nice improvement.

flake8 can help.

You can check PEP8 with Continuous Integration (Travis CI for example)

See for example https://github.com/scls19fr/windrose/blob/master/.travis.yml

https://medium.com/python-pandemonium/what-is-flake8-and-why-we-should-use-it-b89bd78073f2

Kind regards

[scls19fr]

This is probably the first issue to tackle.

So you will be able to notice (when fixing others issues) if you (or anyone submitting a PR) don't decrease code quality

[getsanjeev]

@scls19fr okay this would be my priority.