I just wrote my own... Seems like adding an entire library for this is definitely overkill.

    var emojify = function(message) {
        var codes = [
          '\ud83c[\udf00-\udfff]',
          '\ud83d[\udc00-\ude4f]',
          '\ud83d[\ude80-\udeff]'
        ];
        return message.replace(new RegExp(codes.join('|'), 'g'), '<span class="emoji">$&</span>');
      }

Edit: If this isn't clear, you'd then define an emoji based font family for the `emoji` CSS class. This means no image based emoji and therefore no colour, but IMO it's much simpler and actually more visually pleasing (black and white forces smarter emoji designs).