Getting the plugin started (NAWQAAN-361)

Initially I wrote this as a jasmine spec because I was making assertions on canvas using [jsimagediff](https://github.com/HumbleSoftware/js-imagediff) but the tests ended up being pretty breakable -- results were very dependent on which browser / phantomjs you were using. Minor browser updates to the canvas api that result in a pixel of difference could break tests. Yuck!

I'd like to move these to a demo file too.