see also previous commit
Also updates `scripting_intro.rst` to use literal includes, and uses individual image outputs to avoid the intermediary `.tex` file to join them all.
Images now included relative to the `docs/source` folder instead of the rst file.
Also makes sure to add the updated `yosyshq.css` (which as a sidenote has ended up as `custom.css` in most of the other docs).
