Clean up comments, adding inputs/output docs

* Only code change is refactoring src/row.coffee to its own file
* Remove old comment style which doesn't have any content
* Organize inputs/outputs into separate blocks
* Once this is merged, I will copy the wording to the docs pages
  * Ideally we'd add a generate-docs command to grunt, but this is too
    hard to justify doing right now.

@bigsley @Dylnuge 
Two lines of space seems excessive? Is the comment on [R130](https://github.com/Addepar/ember-table/pull/210/files#diff-cb807d38d2d9952c9d7145ecdd19e9dcR130) refering to the code immediately below it? If yes, there should probably be no space.