Features
- **Breaking**: now `pipe()` does not require argument to be the first value,
instead it is required to use: `pipe(f1, f2, f3, f4)(value)`
- **Breaking**: dropped everything from `returns/__init__.py`,
because we now have quite a lot of stuff
- **Breaking**: dropped support of zero argument functions for `Nothing.fix`
- **Breaking**: dropped support of zero argument functions for `Nothing.rescue`
- `Maybe` now has `.failure()` to match the same API as `Result`
- Adds `identity` function
- Adds `tap` function
- Now `pipe` allows to pipe 8 steps
- Adds `coalesce_result` and `coalesce_maybe` converters
Bugfixes
- Fixes that code inside `.fix` and `.rescue` of `Maybe` might be called twice
Misc
- Now all methods have doctests
- Updates docs about `Success` and `_Success`, `Failure` and `_Failure`
- Updates docs about `pipeline`
- Typechecks async functions and decorators inside `typesafety/` tests