Fs.archive

Fixed
- Mark `TarReadFS` and `ZipReadFS` as case-sensitive filesystems ([12](https://github.com/althonos/fs.archive/issues/12)).
- Fix `TarReadFS` failing to read archives created with dotslash paths ([10](https://github.com/althonos/fs.archive/pull/10)).

Fixed
- `ISOReadFS.__init__` not raising a `CreateFailed` exception when given a file-like handle that is not seekable ([11](https://github.com/althonos/fs.archive/issues/11)).
- `ZipReadFS.isfile` forcefully converting paths to lowercase ([6](https://github.com/althonos/fs.archive/issues/6)).

Changed
- Update minimum version of `py7zr` to `v0.17.3` to support changes in the dictionary returned by `py7zr.SevenZipFile.read`.

Fixed
- `fs.archive.open_archive` not being able to open 7z files ([8](https://github.com/althonos/fs.archive/issues/8)).
- `py7zr.exceptions.Bad7zFile` not being wrapped when thrown in `SevenZipReadFS.__init__`.

Added
- This changelog file.
- `7z` extra for reading and writing 7z archives with the `fs.archive.sevenzipfs` module.

Fixed
- Abstract base classes for collection types being removed from the `collections` module in Python 3.10.
- Handling of Rock Ridge entries in new `pycdlib` versions.
- Namespace handling in `ZipReadFS.scandir` causing `getinfo` to be called when not needed.

Changed
- Use `fs.path.isbase` in `ZipReadFS` to check for implicit directories.
- Use the stdlib implementation of `TarFile.xzopen` on Python 3.

Changed
- Allow all versions of `fs` greater than `v2.2` to work.

Changed
- Bump required `fs` version to `v2.3.0`