In order to make slide_object dumber and and not need to keep track of
slide info, we are moving the business logic to slide_model so that
the model can keep track of whether presentations are ready to switch
and don't need to run reveal_next or something.
This will start to allow us to have a much better data model for the
slides and service items. They can have a type associated with them
and parse which they are from this type.
In order to make this work, I had to determine in rust which were html
and essentially not call the change_slide function and instead call
the reveal_next/previous functions and then tweak it from there.
This object is still unfinished, but it will later serve as our main
object to connect to for the slides that are shown on screen. All of
this needed some heavy tweaking and I still need to learn more about
rust, but the beginnings are there and it will be worth it to have the
safety and speed that rust provides
