Reorder emojis

Emojis are now ordered exactly the same way they are on [the cheatsheet](http://emojicheatsheet.com).

![New smile window](http://i.imgur.com/VTIe7a6.png)

There was one non-existent smiley, called `:fu:` (:fu:). I agree it is a bit rude, but I think it's reasonable to include it here since it's used not only on GitHub, but also on Campfire, Slack and other team messengers out here (and there are teams using it :smirk:).