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#22 

This depends on #35 . Once that's merged, I'll rebase, and this PR will be more manageable.
CoffeeScript takes the `_this` route as well with the "fat arrow" (which is supposed to be part of ES6 :tada:), but in POJS but it is pretty much up for grabs. It's always nice if it can be avoided by naming the variable based on what the actual object is. e.g. if it was some kind of view context, `context` would be cool.

Another route is to use the new `bind` function on functions if you don't need to support older browsers. It basically just generates another closure, so it's easy to do at least a partial polyfill: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/bind#Polyfill