Isort

- Update precommit to default to filtering files that are defined in skip.
- Improved relative path detection for `skip` config usage.
- Added recursive symbolic link protection.
- Implemented 1177: Support for color output using `--color`.
- Implemented recursive symlink detection support.

- Implemented 1335: Official API for diff capturing.
- Implemented 1331: Warn when sections don't match up.
- Implemented 1261: By popular demand, `filter_files` can now be set in the config option.
- Implemented 960: Support for respecting git ignore via "--gitignore" or "skip_gitignore=True".
- Implemented 727: Ability to only add imports if existing imports exist.
- Implemented 970: Support for custom sharable isort profiles.
- Implemented 1214: Added support for git_hook lazy option (Thanks sztamas!)
- Implemented 941: Added an additional `multi_line_output` mode for more compact formatting (Thanks sztamas!)
- Implemented 1020: Option for LOCALFOLDER.
- Implemented 1353: Added support for output formatting plugins.
- ` isort: split` can now be used at the end of an import line.
- Fixed 1339: Extra indent is not preserved when isort:skip is used in nested imports.
- Fixed 1348: `--diff` works incorrectly with files that have CRLF line endings.
- Improved code repositories usage of pylint tags (1350).

- Fixed issue 1333: Use of wrap_length raises an exception about it not being lower or equal to line_length.
- Fixed issue 1330: Ensure stdout can be stubbed dynamically for `show_unified_diff` function.

- Fixed issue 1329: Fix comments duplicated when --fass option is set.

- Fixed issue 1219 / 1326: Comments not wrapped for long lines
- Fixed issue 1156: Bug related to isort:skip usage followed by a multiline comment block

- Fixed issue 1322: Occasionally two extra newlines before comment with `-n` & `--fss`.
- Fixed issue 1189: `--diff` broken when reading from standard input.