Add asciinema-scripted to the list of integrations

[robmoss]

I've been using asciinema to record terminal sessions for online training materials since early last year (here's one example). The ability to record and play back these sessions (and to pause the recording and copy text) is fantastic. Thank you very much!

For longer, more complex examples, I wanted the ability to script the input and automatically insert markers and comments, so I've written a relatively simple Python package called asciinema-scripted.

This PR adds asciinema-scripted to the Integrations page.

This` tool allows you to record scripted terminal sessions, and provides the following features:

• Terminal input is predefined, so that you can avoid typing mistakes (similar to autorecorder);

• Input speed can be controlled, so that viewers can easily follow the input;

• Input delays can be sampled at random, to mimic human typing;

• Markers are defined relative to input events, so their times are calculated automatically;

• Comments can be displayed in a "subtitle" bar at the top or bottom of the terminal — a feature introduced by asciinema-comment.