Kinda finished with intro to Raphael.js for now

- Next step will be filling the why section
  and describing what svg is
Clearing paper after each slidechange
Dynamic insertion/removal of iframes for better performance.

- Also building the finishing slides
Presentation appears good to go.

- I like what I have for now,
  and recon it'd be enough,
  if I review the presentation some days before the nook.
- I added pea.jpg which is an image I made myself,
  and can therefore be published under the MIT License aswell.