Pylivestream

Thanks to HarukiGrande for "shuffle" feature, when making a playlist

increased test coverage

becoming more object-oriented / abstract with FFmpeg

* Greatly increase computational efficiency by appropriately throttling input acquisition rate on files. Devices remain throttled by their own hardware. This can make a 10x reduction in CPU use, while making the stream more stable.
* make fileIn also able to stream to multiple sites. This requires some assumptions about the file streams. For now, it assumes the first video and first audio stream in the file are desired. If this becomes an issue, we can make it configurable in the future by INI file.
* make buffer size a little smaller so that throttling is computed more accurately.

* reoptimize audio + still image data bandwidth, to not be too conservative and fall below minimum recommended bandwidth
* add Microphone broadcast program.

Demos:
* [YouTube](https://www.youtube.com/watch?v=gRHV2t_aSNo&feature=youtu.be&t=20s)
* [Periscope](https://www.periscope.tv/w/1rmxPmowaYYKN)

Further increased robustness with MyPy type hinting validation.

Now self-test actually streams to `/dev/null` to increase test coverage.

Fixed several corner cases as a result

* BUGFIX: handling no video streams from audio files, increased test coverage to include video AND audio files
* broke up modules into separate files for easier readability and code reuse, maybe even different frontends someday (non-FFmpeg) if one should so desire.
* increase robustness of tests and can't find FFmpeg errors

Some may like to input stream keys directly in the "key:" field of *.ini. This release allows you to enter a filename containing only the hexadecimal key, or the key itself.