Evaluate use of https://asciinema.org/ in our docs

[hamishwillee]

The tool https://asciinema.org/ allows lightweight recording of terminal sessions on Linux/Mac OSX that can be embedded in docs and played back.

Evaluate whether these might be useful in our documentation set.

[hamishwillee]

Initial thinking is that for most use cases where you need to display text for users the most important thing is that they can copy-paste the commands. I don't see much benefit in watching the process of someone typing something in.

The exception is where the process itself is of interest. For example showing what it looks like when you successfully connect over MAVProxy is actually useful, because it not only shows the sort of messages you might see, but it shows how long it might take to connect.

I am happy to try this out, but I think this is low priority compared to getting a full document set in place.