Reduce size of pep8speaks config file

[matthewturk]

After pep8speaks-org/pep8speaks#106 has been merged, it looks like we can reduce the config file presence -- and reduce duplication -- for pep8speaks.

I believe it would be sufficient to remove our .pep8speaks.yml file, but we should investigate if we can remove the "ignore" and "exclude" sections and leave the bits where we define how the bot should talk.

[brittonsmith]

Looks like the PR has now been merged. Someone can give this a try if they like.

[matthewturk]

@brittonsmith Excellent! I think this would be a great first-time contribution...

[neutrinoceros]

Closing as we stopped using pep8speak for a little while now