Add support for reveal.js-tableofcontents?

[errosica]

Could you please add support for reveal.js-tableofcontents?

See https://github.com/naamor/reveal.js-tableofcontents

[apreshill]

Duplicate: #80

[cderv]

We could also add support for --toc argument from Pandoc - Followed in #123

it seems simpler to rely on Pandoc own support that to add a specific plugin support just for that. I believe the result would even be better as the TOC will link to the slide - which does not seem the case with the plugin:
https://naamor.github.io/reveal.js-tableofcontents/#/1

So we will probably go with #123 and not this but it could be added if we manage to open support for #80