Add revealjs slides support

[luiscachog]

Not sure if it on the roadmad yet, but it will be cool if the theme supports RevealJS slides.

Expected Behavior

The expected behavior is to have a layout as the one shows it on: https://mjvo.github.io/course-stub/slides/
Basically shows an index for the slides, and when we click on it, shows the slide on revealjs.
My understanding is that the revealjs part is processed by the suib-theme "reveal-hugo"

Current Behavior

N/A

Possible Solution

Reply/Migrate some of the layouts/css/html and adapt them to this theme.

Steps to Reproduce or Template with Error (for bugs)

Context

Your Environment

Hugo Version: 0.54.0

**Browser:**65.0.1

**Desktop or Mobile:**Ubuntu Linux Desktop

Link to your project:

[pacollins]

This theme is low development due to the fact I have gotten a job that prevents me from actively maintaining it and I don't have control to give other collaborators pull access. I am working on making a slimmer version of the site that utilizes CSS Grid, but it is not completed yet.

This can be achieved via customjs.

[luiscachog]

Hello @pacollins,

Terribly sorry on the delay, I already "create" the functionability. You can verify it on https://luiscachog.io/slides/.
However it is improvable :)

The pull request is ready, probably I need to polish my commits, but as you mentioned I noticed that lots of pull requests are not approved yet.

Let me know how can I help!

Thanks