Require conformance to style standards

[hugovk]

Fixes #129.

Checklist

• I have made a material change to the repo (functionality, testing, spelling, grammar)
• I have read the [Contribution Guide] and my PR follows them.
• I updated my branch with the master branch.
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation about the functionality in the appropriate .md file
• [n/a] I have added in line documentation to the code I modified

Short description of what this PR does:

• Include PR Create dummy files to fix tests #130 so CI doesn't fail
• pep8 is now pycodestyle: Please rename this tool PyCQA/pycodestyle#466
• Install and run pyflakes and pycodestyle on CI
• Fix pyflakes and pycodestyle errors in code
• Drop support for EOL Python 3.2 (since 2016-02-27), pyflakes doesn't support it and will fail the build

[thinkingserious]

Hello @hugovk,

Thanks again for the PR!

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