flake8, ref #8

[nim65s]

Hi again,

This PR follows #61, after I found out that some python scripts might not work on python 3.

Then, to ensure that there is no syntax errors on those script neither in python2 nor 3, I used the flake8 linter with python2 -m flake8 and python3 -m flake8.

Most changes are:

• whitespaces, around operators, after a #, and some tabs have been replaced by spaces. To see this PR more clearly, you can ignore this by adding ?w=1 at the end of the url
• using the print function
• removing unused imports
• splitting lines that are too long

[nim65s]

NB: flake8 still complains a bit about function name should be lowercase, but I did not want to change any functionality in the code

[stephanemagnenat]

Thank you for your PR!

Using tabs instead of whitespaces is the Enki/Aseba style. Similarly, keeping relatively long lines is as well, as most editors have good soft warp. At that point, I do not want to change this style as it has been working well for a long time, and re-indenting everything would both loose the blame history and break ongoing refactoring in the ecs-refactor branch.

Can you please submit a PR with only the necessary changes (e.g. changes in print) and no style change? Thank you!