Ffpb

Fixed
- Unneeded decoding in main loop causing codec issues ([22](https://github.com/althonos/ffpb/issues/22)).

Added
- Support for Windows platform ([21](https://github.com/althonos/ffpb/pull/21)).

Removed
- [sh](https://pypi.org/project/sh) dependency.

Added
- Option to change progress bar class in `ffpb.main`.

Fixed
- Decoding error caused by missing encoding in `ffpb.main` ([17](https://github.com/althonos/ffpb/issues/17)).

Added
- Python 3.7 as an explicitly supported version.

Fixed
- Incorrect decoding of filenames caused by [`chardet`](https://pypi.org/project/chardet/).

Fixed
- `ffpb.main` not using given `argv` argument ([12](https://github.com/althonos/ffpb/pull/12)).

Fixed
- `ffpb` crashing on non-video input/output ([8](https://github.com/althonos/ffpb/issues/8)).