Putting the slide dsl code on the main module

* first attempt, seems to work
* fun fact, I just set up a new OS and forgot my IDE and was
  in the metro, so this has been programmed with a bare bones
  gedit - hope it's still ok =)
* It's kinda weird that the slides dsl works but we instance_eval
  the configuration - but I guess it is alright
* looks good, does it? Minimizing pollution while keeping the
  basic evaluation good :)

@jasonrclark review me maybe? Will probably merge tomorrow-ish, though, as I might need it for my talk :)