Provide ffprobe JSON output for RSpec fixtures

Additionally, refactor the Open3 stub methods to provide the corrected
stdout vs stderr. ffprobe provides its output on stdout instead of
stderr which is where it had been retreived previously.
ffprobe does not encounter these complexities

Because ffprobe does not return a decimal frame per second and instead
returns a rational number there is no need for this test.

Also, the colorspace returned in its own field. Therefore, regular
expression gymnastics are no longer requred.
Update impossible SAR spec
Cannot replicate any crashes related to ISO-8859-1

Because I cannot replicate any crashes related to ISO-8859-1 charachters
in the outputs. I am removing these tests.
Provide FFMPEG::Movie#audio_channels from ffprobe
Refactor unsupported audio codec for ffprobe
FFMPEG::MOVIE#frame_rate is now a Rational number
Updated audio for ffprobe
more cleaning
Handle rotated videos from ffprobe
Handle empty movie from ffprobe
Handle weird DAR from ffprobe
Handle irrational FFMPEG::Movie#frame_rate
Different units kb/s to bit/s