Isort

- Fixed 1507: in rare cases isort changes the content of multiline strings after a yield statement.
- Fixed 1505: Support case where known_SECTION points to a section not listed in sections.

- Fixed 1488: in rare cases isort can mangle `yield from` or `raise from` statements.

- Fixed 1469: --diff option is ignored when input is from stdin.

- Fixed 1454: Ensure indented import sections with import heading and a preceding comment don't cause import sorting loops.
- Fixed 1453: isort error when float to top on almost empty file.
- Fixed 1456 and 1415: noqa comment moved to where flake8 cant see it.
- Fixed 1460: .svn missing from default ignore list.

- Fixed 1398: isort: off comment doesn't work, if it's the top comment in the file.
- Fixed 1395: reverse_relative setting doesn't have any effect when combined with force_sort_within_sections.
- Fixed 1399: --skip can error in the case of projects that contain recursive symlinks.
- Fixed 1389: ensure_newline_before_comments doesn't work if comment is at top of section and sections don't have lines between them.
- Fixed 1396: comments in imports with ";" can keep isort from recognizing import line.
- Fixed 1380: As imports removed when `combine_star` is set.
- Fixed 1382: --float-to-top has no effect if no import is already at the top.
- Fixed 1420: isort never settles on module docstring + add import.
- Fixed 1421: Error raised when repo contains circular symlinks.
- Fixed 1427: noqa comment is moved from star import to constant import.
- Fixed 1444 & 1445: Incorrect placement of import additions.
- Fixed 1447: isort5 throws error when stdin used on Windows with deprecated args.
- Implemented 1397: Added support for specifying config file when using git hook (thanks diseraluca!).
- Implemented 1405: Added support for coloring diff output.
- Implemented 1434: New multi-line grid mode without parentheses.

Goal Zero (Tickets related to aspirational goal of achieving 0 regressions for remaining 5.0.0 lifespan):
- Implemented 1392: Extensive profile testing.
- Implemented 1393: Proprety based testing applied to code snippets.
- Implemented 1391: Create automated integration test that includes full code base of largest OpenSource isort users.

Potentially breaking changes:
- Fixed 1429: --check doesn't print to stderr as the documentation says. This means if you were looking for `ERROR:` messages for files that contain incorrect imports within stdout you will now need to look in stderr.

- Fixed 1383: Known other does not work anymore with .editorconfig.
- Fixed: Regression in first known party path expansion.