Update isort to 4.3.11

[pyup-bot]

This PR updates isort from 4.3.9 to 4.3.11.

Changelog

4.3.11

- Fixed issue 876: confused by symlinks pointing to virtualenv gives FIRSTPARTY not THIRDPARTY
- Fixed issue 873: current version skips every file on travis
- Additional caching to reduce performance regression introduced in 4.3.5

4.3.10

- Fixed Windows incompatibilities (Issue 835)
- Fixed relative import sorting bug (Issue 417)
- Fixed "no_lines_before" to also be respected from previous empty sections.
- Fixed slow-down introduced by finders mechanism by adding a LRU cache (issue 848)
- Fixed issue 842 default encoding not-set in Python2
- Restored Windows automated testing
- Added Mac automated testing

Links

• PyPI: https://pypi.org/project/isort
• Changelog: https://pyup.io/changelogs/isort/
• Repo: https://github.com/timothycrosley/isort

[pyup-bot]

Closing this in favor of #49