Add segment muxer output

[SinisterMaya]

This adds support for the segment output muxer that allows to generate several files instead of only one. Ideal when you don't want to handle too heavy files or when you need to maintain a history of streams. https://ffmpeg.org/ffmpeg-formats.html#segment_002c-stream_005fsegment_002c-ssegment

[BaileyMillerSSI]

This would be an awesome improvement for some code that I am working on that uses segmenting. I've had to just string together a bunch of custom arguments but having this fluent syntax would be great!

[rosenbjerg]

Hey @SinisterMaya I have fixed the unrelated problems with CI, but Video_MultiOutput_With_Segmented_File_Output is failing. Would you mind taking a look?