Faster Whisper from PyPI, Better Word Timestamps, Fix JSON Load

Pull in faster-whisper directly from PyPI, new faster-whisper lib also pulled in the base library's changes to allow word level timestamps (we no longer have to linearly interpolate! Finally, this is an attempt to fix a JSON decode error during config reading.

What's Changed

• docs/improve-dev-infra-setup by @isaacna in #229

Full Changelog: v4.0.0...v4.0.9.rc0