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Mostly almost working (one big issue: [the controller isn't properly sorting](https://github.com/gschorkopf/frolfr/commit/51eb225315de699c2de8e41bcafda858911a9543)... thoughts?). Open to suggestions on code quality

@sebastiangeiger @killpack  @pdougall1 

![screen shot 2014-12-11 at 4 12 56 pm](https://cloud.githubusercontent.com/assets/2623668/5402210/27bc519a-8150-11e4-9bc7-b808e96b65d5.png)

(Thought process: in the docs for `ArrayController.sortProperties`, it says: "Specifies which properties dictate the arrangedContent's sort order." So I'm thinking `content` will return the model, whereas `arrangedContent` will return the model sorted by your specified sort properties.)