Fixes typo that made makeTable crash

I was trying out the examples, but makeTable didn't work. Figured out that there was a typo in the [May 9th update](https://github.com/jlord/sheetsee-tables/commit/f36d53cb053c14e4060b75b75ab7f501c5dd3c94). [Screenshot with some info](http://i.imgur.com/NHTnASl.png).

ps: paper trail, [original pull](https://github.com/jlord/sheetsee.js/pull/49) I (should not have :D) made in the sheetsee.js repo
pps: loving sheetsee, hope to contribute an example soon