Resolve JS hint errors

Minor touch up so it passes validation
@akhoury and I poured over this, and we don't see any real problems here.  I was more worried about the exception, but I think that's just from you pasting that line into a browser console, which wouldn't work because it's not called in the context of a function arguments.  

While the code paths work in the browser and in node without any errors, I don't like the current solution because of the complex behavior of the 'context' variable even when it's not being used. There's an implied bug there. =) For example, I could see the script failing if someone was running csv.js in node without require, perhaps built into a larger script.    Both the new and old (the Function one) would have had this problem.  I'm not even sure why the anon function was used when simply passing in 'this' would have achieved the same goal in the browser code path.

I'll clean it up -- please let me know if bails in any way.  I'll also note that I need to create a node-compatible unit test.