Ffmpeg-normalize

* Allow cover art in MP3.

* Remove warning for short files (87)

* Building on Windows failed due to character conversion (244)

* Docs: add HighMans as a contributor for code (242)

* docs: update README.md

* docs: update .all-contributorsrc

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* Properly handle non-existing input files and skipping.

* Fix: Dockerfile used wrong path.

* Use `https` rather than `http` (238)

* Docs: add psavva as a contributor for code (236)

* docs: update README.md

* docs: update .all-contributorsrc

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* Add Docker support (235)

* Docs: add sian1468 as a contributor.

* Round percentage in test (234)

* Bump ffmpeg-progress-yield, round percentage output.

* Fix test for progress.

seems flaky, worked locally?

* Bump ffmpeg-progress-yield, output progress in percent.

* Docs: add 07416 as a contributor.

* A typo in README (231)