Remove segments of video where nothing is happening in terminal

This adds a Python script that constructs and runs the ffmpeg commands to:

Detect segments in the video where the screen is still / terminal output not moving.
Shortens these segments to speed up the video.

Note: if the result is still longer than Twitter's max limit of 140 seconds, the Twitter version gets sped up further.

Github workflow updated to run this when new builds are added. See test run in my fork.

Before (without speedup):

Now (with speedup):

coinkite / bitcoinbinary.org