Update brotli to 1.0.8

[pyup-bot]

This PR updates brotli from 1.0.7 to 1.0.8.

Changelog

1.0.8

SECURITY: decoder: fix integer overflow when input chunk is larger than 2GiB

Other changes:
* add support WASM (emscripten) build
* `brotli -v` now reports raw / compressed size
* build files / docs maintenance
* reduce sources tarball size
* decoder: minor speed / memory usage improvements
* encoder: fix rare access to uninitialized data in ring-buffer
* encoder: improve support for platforms that does not have `log2`
* encoder: better support for MSVC (replacement for `__builtin_clz` and `__builtin_ctzll`
* python: `decompress` now reports error if there is unused after the end of compressed input

Links

• PyPI: https://pypi.org/project/brotli
• Changelog: https://pyup.io/changelogs/brotli/
• Repo: https://github.com/google/brotli

[pyup-bot]

Closing this in favor of #79