Code listings

[ascholerChemeketa]

This implements title (not caption!) at the top of listings in HTML. Latex left as an exercise for the reader.

It also implements program/console pairs in listings. The console will only be displayed if the program does not become and activecode - so you can author a sample run that shows in static output but not when the user can just run the code themselves.

Currently, I steal the listing number to put a "subtitle" on the console that looks like:
Sample run of Listing 2.3.1

There is enough markup around it and the rest of the content that a theme should be able to do fancy visual things, including hiding that chunk of text, with the program/subtitle/console.

[rbeezer]

Latex left as an exercise for the reader.

I can attempt that, but it means a delay as it goes into the queue.

It also implements program/console pairs in listings.

This sounds like a different change (though I have not looked closely). Please split this PR into two discrete tasks, I can't manage reviews, changes, repackaging, LaTeX additions when a PR does two things.

Currently, I steal the listing number to put a "subtitle" on the console that looks like:

On pretext-dev, I wrote:

(b) I'm reluctant to stick an author with a defalt title/heading that may not be what they are really after.

There is enough markup around it and the rest of the content that a theme should be able to do fancy visual things, including hiding that chunk of text, with the program/subtitle/console.

We don't always have this flexibility in other formats.

[ascholerChemeketa]

Just did a force push that removes the program|console combined. This now solely focuses on listing having a title instead of caption and it appearing above the listing itself.

Added latex and braille handling. Latex output looks good, unsure how to test braille.