clean up some unnecessary files

[guihao-liang]

• .flake8.log we don't need to track it in our repo.
• black doesn't need to check py38.
• ignore .pre-commit-config.yaml so that one can have their own customized pre-commit config living together with the repo.

[guihao-liang]

intentionally ignore,

• E501, line too long
• E266 too many leading '#' for block comment
• temporarily ignore all init.py files

flake8 src/python/turicreate --config=tox.ini | wc -l
   864

[TobyRoseman]

Do we want to add instructions for running flake8 to our build document?

Do we want to add flake8 to our development requirements.txt?

[TobyRoseman]

I don't think you need to list E501 twice.

[guihao-liang]

Yeah, my oversight.

[TobyRoseman]

I don't really think this comment is really adding anything. I'd probably prefer just not having a comment here than having this comment. A better comment might be # git hooks.

[guihao-liang]

That's better! Will do.

[guihao-liang]

Do we want to add instructions for running flake8 to our build document?

Do we want to add flake8 to our development requirements.txt?

No, this flake8 is only used by pre-commit hooks and also personal use. Currently, there are too many things that we need to fix in order to use flake8.