Iotoolz

- Force `requests` to be `>=2.26.0,<3.0` because of `chardet` LGPL licensing (See https://github.com/psf/requests/pull/5797)
- Make `chardet` optional because of LGPL licensing. Defaults to `charset_normalizer` if `chardet` is not installed.
- Added `readable` method to AbcStream

- Fix bug in resolving bucket for `minio://` schema

- Added `MinioStream` (`minio://`)
- Added `seekable` method for AbcStream

- Fix system markers for windows so that python-magic is installed correctly on windows machine.

- Loosen the dependencies requirements so that it is more forgiving with older packages (e.g. using an older version of requests).

- `cytoolz` is now an optional package.