Python module import order not being checked about ament_lint

[wjwwood]

+1 for flake8. In the past I suggested it, but I was met with resistance. If I remember correctly something about selecting pep8 without pyflakes, but honestly I think it was just because we already had pep8 and pyflakes separately. I think flake8 is just superior as it has more recent development and newer options. I'd help test and review if you wanted to create a flake8 linter to replace the pep8 and pyflakes linters.

[mikaelarguedas]

Note: just saw that flake8 was absent from install instructions from linux (while in the OSX and Windows instructions). Given that flake8 is installed via pip on all other platform should we add it to the packages install via pip on the linux instructions page?

[codebot]

ideas to move forward:

• detect if it's flake8-v2 and disable (at very least) rather than blow up
• on farm, remove from apt line (if necessary) and add to pip to get flake8-v3

[mikaelarguedas]

closing this now that all PRs have been merged