Update PEP8.

Summary: Update `pep8.py` from v1.3.4 to v1.5.7. Because why not?

Test Plan: N/A

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D9412
Fix "array to string" conversion error.

Summary: Fixes T5298. This bug was probably introduced in D9248. It looks like I forgot to update some references to `$version`.

Test Plan: Ran `arc lint --everything` in rPHU.

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: epriestley, Korvin

Maniphest Tasks: T5298

Differential Revision: https://secure.phabricator.com/D9434
Lint the `ArcanistSpellingDefaultData` class.

Summary:
Currently, the `ArcanistSpellingDefaultData` is marked with a `@nolint` annotation. This means that it doesn't get linted by any linters. Really, the intention here was to make sure that this file isn't linted by the `ArcanistSpellingLinter` linter.

Now that the `.arclint` file is more mature, we can easily just exclude this file from being linted //only// by the spelling linter, whilst allowing other linters to run.

Test Plan: Ran `arc lint`.

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D9432
Allow spaces after the `.` operator if followed by a comment.

Summary: Currently, `'foo'.    // Some comment` is not allowed by the `ArcanistXHPASTLinter::LINT_BINARY_EXPRESSION_SPACING` rule. I believe that in the case of a trailing comment, we //should// allow whitespace after the `.` operator.

Test Plan: Wrote and executed a unit test for this case.

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley, #blessed_reviewers

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D9438
Merge branch 'master' of github.com:facebook/arcanist