Replace all instances of JQuery $.each with LoDash _.forEach

Should improve readability, and seems cleaner to me.

More of an opinion, though. This also removes dependability on having the index be initialized in options (before the actual array element).

If we need to use the index, it can be added as the second parameter: `(value, index|key, collection)`. Taken from [this Lodash JSDoc](https://github.com/lodash/lodash/blob/master/lodash.js#L4922).