add underscore.js depency

[David Greisen]

Now that we have had to give up concise and expressive coffeescript for javascript, I think a toolkit of often needed functions would be incredibly helpful. I suggest underscore.js which provides a plethora of useful functions for manipulating and inspecting collections, arrays, objects and functions, all at under 5kb.

Thoughts @josephg?

[Jeremy Rose]

My 2¢: not worth it. In my experience, when I encounter _.js in other apps, it takes me extra time reading to figure out exactly what the semantics of _'s functions are. Raw JS may be wordier, but it is lingua franca, and isn't that the point of using JS in the first place?

(My preferred solution is to just use CoffeeScript...)

[Seph Gentle]

Agree - I just don't think underscore buys us enough to be worth it. I'm considering pulling in async on the server though.

[David Greisen]

I thought that might be the case, but figured I'd give it a shot.