Blacksin

- don't remove single empty lines outside of bracketed expressions (19)

- added ability to pipe formatting from stdin to stdin (25)

- restored ability to format code with legacy usage of `async` as a name (20, 42)

- even better handling of numpy-style array indexing (33, again)

- changed positioning of binary operators to occur at beginning of lines instead of at
the end, following
[a recent change to PEP 8](https://github.com/python/peps/commit/c59c4376ad233a62ca4b3a6060c81368bd21e85b)
(21)

- ignore empty bracket pairs while splitting. This avoids very weirdly looking
formattings (34, 35)

- remove a trailing comma if there is a single argument to a call

- if top level functions were separated by a comment, don't put four empty lines after
the upper function

- fixed unstable formatting of newlines with imports

- fixed unintentional folding of post scriptum standalone comments into last statement
if it was a simple statement (18, 28)

- fixed missing space in numpy-style array indexing (33)

- fixed spurious space after star-based unary expressions (31)

- added `--check`

- only put trailing commas in function signatures and calls if it's safe to do so. If
the file is Python 3.6+ it's always safe, otherwise only safe if there are no `*args`
or `**kwargs` used in the signature or call. (8)

- fixed invalid spacing of dots in relative imports (6, 13)

- fixed invalid splitting after comma on unpacked variables in for-loops (23)

- fixed spurious space in parenthesized set expressions (7)

- fixed spurious space after opening parentheses and in default arguments (14, 17)

- fixed spurious space after unary operators when the operand was a complex expression
(15)

- first published version, Happy 🍰 Day 2018!

- alpha quality

- date-versioned (see: https://calver.org/)