Sphinx can syntax-highlight a block if we use the right syntax.

Reviewed-by: Eric Engestrom <eric@engestrom.ch>
Part-of: <!4630>

This uses the previously added scripts to convert the documentation to
reStructuredText, which is both easier to read offline, and can be used
to generate modern HTML for online documentation.

No modification to the generated results have been done.

Acked-by: Eric Engestrom <eric@engestrom.ch>
Part-of: <!4630>