Mostly in the `more_scripting` section, with part of the intro in the `scripting_intro`.
Also includes an extra todo on the installation page and some extra notes on where to find `show` details where relevant.
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).
Fix#3905 by removing emoji (and move the comment into the if block for less ambiguity).
Adds `latexmk` to README.
Note that latexpdf doesn't seem to like `cmd:ref` links, possibly because the
reference location is inside a latex comment block, but I was under the
impression that there was a reference location in there previously which was
working fine. May be related to how the `cmd:def` block expands (or doesn't as
the case may be).